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Use of models in large-area forest surveys: comparing model-assisted, model-based and hybrid estimation / Göran Stahl in Forest ecosystems, vol 3 (2016)
[article]
Titre : Use of models in large-area forest surveys: comparing model-assisted, model-based and hybrid estimation Type de document : Article/Communication Auteurs : Göran Stahl, Auteur ; Svetlana Saarela, Auteur ; Sebastian Schnell, Auteur ; Sören Holm, Auteur ; et al., Auteur Année de publication : 2016 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] échantillonnage
[Termes IGN] estimation statistique
[Termes IGN] inférence statistique
[Termes IGN] inventaire forestier (techniques et méthodes)
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) This paper focuses on the use of models for increasing the precision of estimators in large-area forest surveys. It is motivated by the increasing availability of remotely sensed data, which facilitates the development of models predicting the variables of interest in forest surveys. We present, review and compare three different estimation frameworks where models play a core role: model-assisted, model-based, and hybrid estimation. The first two are well known, whereas the third has only recently been introduced in forest surveys. Hybrid inference mixes design-based and model-based inference, since it relies on a probability sample of auxiliary data and a model predicting the target variable from the auxiliary data..We review studies on large-area forest surveys based on model-assisted, model-based, and hybrid estimation, and discuss advantages and disadvantages of the approaches. We conclude that no general recommendations can be made about whether model-assisted, model-based, or hybrid estimation should be preferred. The choice depends on the objective of the survey and the possibilities to acquire appropriate field and remotely sensed data. We also conclude that modelling approaches can only be successfully applied for estimating target variables such as growing stock volume or biomass, which are adequately related to commonly available remotely sensed data, and thus purely field based surveys remain important for several important forest parameters. Numéro de notice : A2016--161 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1186/s40663-016-006 En ligne : https://doi.org/10.1186/s40663-016-0064-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=87015
in Forest ecosystems > vol 3 (2016)[article]Utilisation d’une source laser pulsée à haute energie comme source acoustique large bande en milieu liquide / Jean-Pierre Sessarego in Traitement du signal, vol 33 n° 1 (2016-1)
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Titre : Utilisation d’une source laser pulsée à haute energie comme source acoustique large bande en milieu liquide Type de document : Article/Communication Auteurs : Jean-Pierre Sessarego, Auteur ; Régine Guillermin, Auteur ; Amélie Jarnac, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 95 - 111 Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] laser
[Termes IGN] milieu marin
[Termes IGN] onde acoustique
[Termes IGN] signal acoustique
[Termes IGN] télédétection acoustiqueRésumé : (auteur) Ce travail est relatif à l’étude expérimentale d’un problème d’opto-acoustique non linéaire, consistant à générer un signal acoustique dans l’eau à partir d’un laser pulsé térawatt (TW). La source acoustique obtenue a pu être reliée au phénomène de filamentation qui produit une contraction du faisceau initial, accompagnée de la formation d’un plasma. Des travaux relativement récents ont montré que les lasers de ce type pouvaient être utilisés pour produire des sources acoustiques déportées, avec des applications intéressantes pour l’acoustique sous-marine. Le spectre de la source acoustique obtenue a été étudié à l’aide de plusieurs hydrophones couvrant une très large bande de fréquence, et le diagramme de directivité a été mesuré dans deux plans (plan du filament et plan perpendiculaire au filament). Le niveau acoustique de la source en fonction de l’énergie, de la durée, et de la longueur d’onde de l’impulsion laser, a également été étudié. Numéro de notice : A2016-277 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80834
in Traitement du signal > vol 33 n° 1 (2016-1) . - pp 95 - 111[article]Adaptive GPS/INS integration for relative navigation / Je Young Lee in GPS solutions, vol 20 n° 1 (January 2016)
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Titre : Adaptive GPS/INS integration for relative navigation Type de document : Article/Communication Auteurs : Je Young Lee, Auteur ; Hee Sung Kim, Auteur ; Kwang Ho Choi, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 63 - 75 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] covariance
[Termes IGN] filtre de Kalman
[Termes IGN] GPS-INS
[Termes IGN] intégration de données
[Termes IGN] navigationRésumé : (Auteur) Relative navigation based on GPS receivers and inertial measurement units is required in many applications including formation flying, collision avoidance, cooperative positioning, and accident monitoring. Since sensors are mounted on different vehicles which are moving independently, sensor errors are more variable in relative navigation than in single-vehicle navigation due to different vehicle dynamics and signal environments. In order to improve the robustness against sensor error variability in relative navigation, we present an efficient adaptive GPS/INS integration method. In the proposed method, the covariances of GPS and inertial measurements are estimated separately by the innovations of two fundamentally different filters. One is the position-domain carrier-smoothed-code filter and the other is the velocity-aided Kalman filter. By the proposed two-filter adaptive estimation method, the covariance estimation of the two sensors can be isolated effectively since each filter estimates its own measurement noise. Simulation and experimental results demonstrate that the proposed method improves relative navigation accuracy by appropriate noise covariance estimation. Numéro de notice : A2016-603 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0446-4 En ligne : http://dx.doi.org/10.1007/s10291-015-0446-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81801
in GPS solutions > vol 20 n° 1 (January 2016) . - pp 63 - 75[article]Combining 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)
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Titre : Combining spaceborne SAR images with 3D point clouds for infrastructure monitoring applications Type de document : Article/Communication Auteurs : Andrei Anghel, Auteur ; Gabriel Vasile, Auteur ; Rémy Boudon, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 45 – 61 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image mixte
[Termes IGN] analyse combinatoire (maths)
[Termes IGN] appariement d'images
[Termes IGN] France métropolitaine
[Termes IGN] image radar moirée
[Termes IGN] semis de points
[Termes IGN] test de performance
[Termes IGN] tomographieRésumé : (auteur) The measurement and monitoring of critical infrastructure elements by remote sensing has become necessary for economical and security reasons. Information provided by remote sensing for infrastructure monitoring is extracted with specific signal processing chains that have to be adapted to the geometric particularities of the structure. In this paper we present in detail the first monitoring results obtained by combining spaceborne synthetic aperture radar (SAR) data with externally measured point clouds describing an infrastructure element. The processing core is essentially based on refocusing each available SAR image on the provided point cloud and identifying the scatterers that can be monitored by means of four dimensional tomography. The key points and limitations which appear in the measurement and data processing are illustrated on two test sites in France: the Puylaurent water-dam and the Chastel landslide. The SAR products used are high-resolution sliding spotlight SAR images acquired in the TerraSAR-X and TanDEM-X missions, whereas the point clouds of the structures were generated using GPS localization, topographic measurements and laser scans. The estimated deformations of the scatterers using the SAR images were in good agreement with available in-situ data provided through regular topographic surveys and embedded measuring systems. Numéro de notice : A2016-040 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.11.008 Date de publication en ligne : 17/12/2015 En ligne : https://doi.org/10.1016/j.isprsjprs.2015.11.008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79520
in ISPRS Journal of photogrammetry and remote sensing > vol 111 (January 2016) . - pp 45 – 61[article]Contribution of mass density heterogeneities to the quasigeoid-to-geoid separation / Robert Tenzer in Journal of geodesy, vol 90 n° 1 (January 2016)
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Titre : Contribution of mass density heterogeneities to the quasigeoid-to-geoid separation Type de document : Article/Communication Auteurs : Robert Tenzer, Auteur ; Christian Hirt, Auteur ; Pavel Novák, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 65-80 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] anomalie de pesanteur
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] harmonique sphérique
[Termes IGN] masse de la Terre
[Termes IGN] modèle de densité
[Termes IGN] quasi-géoïde
[Termes IGN] topographieRésumé : (auteur) The geoid-to-quasigeoid separation is often computed only approximately as a function of the simple planar Bouguer gravity anomaly and the height of the computation point while disregarding the contributions of terrain geometry and anomalous topographic density as well as the sub-geoid masses. In this study we demonstrate that these contributions are significant and, therefore, should be taken into consideration when investigating the relation between the normal and orthometric heights particularly in the mountainous, polar and geologically complex regions. These contributions are evaluated by applying the spectral expressions for gravimetric forward modelling and using the EIGEN-6C4 gravity model, the Earth2014 datasets of terrain, ice thickness and inland bathymetry and the CRUST1.0 sediment and (consolidated) crustal density data. Since the global crustal density models currently available (e.g. CRUST1.0) have a limited accuracy and resolution, the comparison of individual density contributions is—for consistency—realized with a limited spectral resolution up to a spherical harmonic degree 360 (or 180). The results reveal that the topographic contribution globally varies between −0.33 and 0.57 m, with maxima in Himalaya and Tibet. The contribution of ice considerably modifies the geoid-to-quasigeoid separation over large parts of Antarctica and Greenland, where it reaches ∼0.2 m. The contributions of sediments and bedrock are less pronounced, with the values typically varying only within a few centimetres. These results, however, have still possibly large uncertainties due to the lack of information on the actual sediment and bedrock density. The contribution of lakes is mostly negligible; its maxima over the Laurentian Great Lakes and the Baikal Lake reach only several millimetres. The contribution of the sub-geoid masses is significant. It is everywhere negative and reaches extreme values of −4.43 m. According to our estimates, the geoid-to-quasigeoid separation globally varies within −4.19 and 0.26 m while the corresponding values computed according to a classical definition are only negative and reach extreme values of −3.5 m. A comparison of these results reveals that inaccuracies caused by disregarding the terrain geometry and mass density heterogeneities distributed within the topography and below the geoid surface can reach ±2 m or more in the mountainous regions. Numéro de notice : A2016-019 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0858-5 Date de publication en ligne : 01/10/2015 En ligne : https://doi.org/10.1007/s00190-015-0858-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79466
in Journal of geodesy > vol 90 n° 1 (January 2016) . - pp 65-80[article]Debunking trickle-down ecosystem services: The fallacy of omnipotent, homogeneous beneficiaries / Raoul Wieland in Ecological economics, vol 121 (January 2016)PermalinkEffects of water and heat on growth of winter wheat in the North China Plain / Hongyan Wang in Geocarto international, vol 31 n° 1 - 2 (January - February 2016)PermalinkEstimating over- and understorey canopy density of temperate mixed stands by airborne LiDAR data / Hooman Latifi in Forestry, an international journal of forest research, vol 89 n° 1 (January 2016)PermalinkÉtat de conservation des habitats : propositions de définitions et de concepts pour l’évaluation à l’échelle d’un site Natura 2000 / Lise Maciejewski in Revue d'écologie, vol 71 n° 1 (janvier - mars 2016)PermalinkFirst results from the GLORIE polarimetric GNSS-R airborne campaign dedicated to land parameters estimation / Erwan Motte (2016)PermalinkForcing scale invariance in multipolarization SAR change detection / Vincenzo Carotenuto in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)PermalinkA function-based linear map symbol building and rendering method using shader language / Songshan Yue in International journal of geographical information science IJGIS, vol 30 n° 1-2 (January - February 2016)PermalinkGAGAN - India’s SBAS : Redefining Navigation over the Indian Region / A.S. Ganeshan in Inside GNSS, vol 11 n° 1 (January - February 2016)PermalinkGeodetic SAR tomography / Xiao Xiang Zhu in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)PermalinkVol 43 n° 1 - January 2016 - GeoVisual analytics: Interactivity, dynamics, and scale (Bulletin de Cartography and Geographic Information Science) / Gennady AdrienkoPermalink