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On the spectral combination of satellite gravity model, terrestrial and airborne gravity data for local gravimetric geoid computation / Tao Jian in Journal of geodesy, vol 90 n° 12 (December 2016)
[article]
Titre : On the spectral combination of satellite gravity model, terrestrial and airborne gravity data for local gravimetric geoid computation Type de document : Article/Communication Auteurs : Tao Jian, Auteur ; Yan Ming Wang, Auteur Année de publication : 2016 Article en page(s) : pp 1405 - 1418 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse harmonique
[Termes IGN] bruit blanc
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] erreur
[Termes IGN] géoïde gravimétrique
[Termes IGN] géoïde local
[Termes IGN] Texas (Etats-Unis)
[Termes IGN] varianceRésumé : (Auteur) One of the challenges for geoid determination is the combination of heterogeneous gravity data. Because of the distinctive spectral content of different data sets, spectral combination is a suitable candidate for its solution. The key to have a successful combination is to determine the proper spectral weights, or the error degree variances of each data set. In this paper, the error degree variances of terrestrial and airborne gravity data at low degrees are estimated by the aid of a satellite gravity model using harmonic analysis. For higher degrees, the error covariances are estimated from local gravity data first, and then used to compute the error degree variances. The white and colored noise models are also used to estimate the error degree variances of local gravity data for comparisons. Based on the error degree variances, the spectral weights of satellite gravity models, terrestrial and airborne gravity data are determined and applied for geoid computation in Texas area. The computed gravimetric geoid models are tested against an independent, highly accurate geoid profile of the Geoid Slope Validation Survey 2011 (GSVS11). The geoid computed by combining satellite gravity model GOCO03S and terrestrial (land and DTU13 altimetric) gravity data agrees with GSVS11 to ±1.1 cm in terms of standard deviation along a line of 325 km. After incorporating the airborne gravity data collected at 11 km altitude, the standard deviation is reduced to ±0.8 cm. Numerical tests demonstrate the feasibility of spectral combination in geoid computation and the contribution of airborne gravity in an area of high quality terrestrial gravity data. Using the GSVS11 data and the spectral combination, the degree of correctness of the error spectra and the quality of satellite gravity models can also be revealed. Numéro de notice : A2016-810 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0932-7 En ligne : http://dx.doi.org/10.1007/s00190-016-0932-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82602
in Journal of geodesy > vol 90 n° 12 (December 2016) . - pp 1405 - 1418[article]Optimizing the spatial resolution of WorldView-2 imagery for discriminating forest vegetation at subspecies level in KwaZulu-Natal, South Africa / Romano Lottering in Geocarto international, vol 31 n° 7 - 8 (July - August 2016)
[article]
Titre : Optimizing the spatial resolution of WorldView-2 imagery for discriminating forest vegetation at subspecies level in KwaZulu-Natal, South Africa Type de document : Article/Communication Auteurs : Romano Lottering, Auteur ; Onisimo Mutanga, Auteur Année de publication : 2016 Article en page(s) : pp 870 - 880 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Afrique du sud (état)
[Termes IGN] classification dirigée
[Termes IGN] espèce végétale
[Termes IGN] image Worldview
[Termes IGN] pouvoir de résolution géométrique
[Termes IGN] rééchantillonnage
[Termes IGN] sous-étage
[Termes IGN] surface forestière
[Termes IGN] varianceRésumé : (Auteur) The objective of this study was to identify an appropriate spatial resolution for discriminating forest vegetation at subspecies level. WorldView-2 imagery was progressively resampled to coarser spatial resolutions. At a compartment level, 30 × 30-m subsets were generated across forest compartments to represent the five forest subspecies investigated in this study. From the centre of each subset, the spatial resolution of the original WorldView-2 image was resampled from 6 to 34-m, with increments of 4-m. The variance was then calculated at every resampled spatial resolution using each of the eight WorldView-2 bands. Based on the sampling theorem, the 3-m spatial resolution provided an appropriate resolution for all subspecies investigated. The WorldView-2 image was subsequently classified using the partial least squares linear discriminant analysis algorithm and the appropriate spatial resolution. An overall classification accuracy of 90% was established with an allocation disagreement of 9 and a quantity disagreement of 1. Numéro de notice : A2016-458 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2015.1094519 Date de publication en ligne : 26/10/2015 En ligne : http://dx.doi.org/10.1080/10106049.2015.1094519 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81382
in Geocarto international > vol 31 n° 7 - 8 (July - August 2016) . - pp 870 - 880[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2016041 RAB Revue Centre de documentation En réserve L003 Disponible Optimal plot size or point sample factor for a fixed total cost using the Fairfield Smith relation of plot size to variance / Thomas B. Lynch in Forestry, an international journal of forest research, vol 90 n° 2 (March 2016)
[article]
Titre : Optimal plot size or point sample factor for a fixed total cost using the Fairfield Smith relation of plot size to variance Type de document : Article/Communication Auteurs : Thomas B. Lynch, Auteur Année de publication : 2016 Article en page(s) : pp 211 - 218 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] coût
[Termes IGN] placette d'échantillonnage
[Termes IGN] surface terrière
[Termes IGN] variance
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Using the classical power function relationship between inverse plot size and sample variance, the method of Lagrangian multipliers was applied to minimize the variance of the sample mean among measurements on sample plots (e.g. volume or basal area per hectare) subject to a fixed total cost with varying plot size and sample size. This results in equations that can be used to determine optimal plot and sample size for a fixed total cost. The method does not require a prior estimate of variance. Optimal point sampling basal area factor can be substituted for plot size if variance and cost functions are available for point sampling. It was determined theoretically that no feasible optimum solution exists if the ratio of the relative change rate in variance to the relative change rate in cost per plot is less than negative one. This occurs because in that case the variance as a function of plot size is being reduced faster than the cost per plot is increasing in relative terms. An example application based on cost and variance functions from the literature found that the optimal surface was quite flat, so that an optimum existed but a rather wide range of plot and sample size combinations were close to optimum for a fixed total cost. In practical terms this means that a wide range of plot sizes would give nearly equal precision for a fixed total cost in this example. This may not be the case for all realistic parameterizations of the cost functions. Numéro de notice : A2016--135 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1093/forestry/cpw038 En ligne : https://doi.org/10.1093/forestry/cpw038 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85777
in Forestry, an international journal of forest research > vol 90 n° 2 (March 2016) . - pp 211 - 218[article]Statistical rigor in LiDAR-assisted estimation of aboveground forest biomass / Timothy G. Gregoire in Remote sensing of environment, vol 173 (February 2016)
[article]
Titre : Statistical rigor in LiDAR-assisted estimation of aboveground forest biomass Type de document : Article/Communication Auteurs : Timothy G. Gregoire, Auteur ; Erik Naesset, Auteur ; Ronald E. McRoberts, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 98 - 108 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] biomasse aérienne
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] échantillonnage
[Termes IGN] incertitude géométrique
[Termes IGN] inférence statistique
[Termes IGN] varianceRésumé : (auteur) For many decades remotely sensed data have been used as a source of auxiliary information when conducting regional or national surveys of forest resources. In the past decade, airborne scanning LiDAR (Light Detection and Ranging) has emerged as a promising tool for sample surveys aimed at improving estimation of above-ground forest biomass. This technology is now employed routinely in forest management inventories of some Nordic countries, and there is eager anticipation for its application to assess changes in standing biomass in vast tropical regions of the globe in concert with the UN REDD program to limit C emissions. In the rapidly expanding literature on LiDAR-assisted biomass estimation the assessment of the uncertainty of estimation varies widely, ranging from statistically rigorous to ad hoc. In many instances, too, there appears to be no recognition of different bases of statistical inference which bear importantly on uncertainty estimation. Statistically rigorous assessment of uncertainty for four large LiDAR-assisted surveys is expounded. Numéro de notice : A2016--160 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2015.11. En ligne : https://doi.org/10.1016/j.rse.2015.11.012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=87012
in Remote sensing of environment > vol 173 (February 2016) . - pp 98 - 108[article]Development, calibration and evaluation of a portable and direct georeferenced laser scanning system for kinematic 3D mapping / Erik Heinz in Journal of applied geodesy, vol 9 n° 4 (December 2015)
[article]
Titre : Development, calibration and evaluation of a portable and direct georeferenced laser scanning system for kinematic 3D mapping Type de document : Article/Communication Auteurs : Erik Heinz, Auteur ; Christian Eling, Auteur ; Markus Wieland, Auteur ; Lasse Klingbeil, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2015 Article en page(s) : pp 227 - 243 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] étalonnage d'instrument
[Termes IGN] géoréférencement direct
[Termes IGN] semis de points
[Termes IGN] système de numérisation mobile
[Termes IGN] télémètre laser
[Termes IGN] varianceRésumé : (auteur) In recent years, kinematic laser scanning has become increasingly popular because it offers many benefits compared to static laser scanning. The advantages include both saving of time in the georeferencing and a more favorable scanning geometry. Often mobile laser scanning systems are installed on wheeled platforms, which may not reach all parts of the object. Hence, there is an interest in the development of portable systems, which remain operational even in inaccessible areas. The development of such a portable laser scanning system is presented in this paper. It consists of a lightweight direct georeferencing unit for the position and attitude determination and a small low-cost 2D laser scanner. This setup provides advantages over existing portable systems that employ heavy and expensive 3D laser scanners in a profiling mode. A special emphasis is placed on the system calibration, i. e. the determination of the transformation between the coordinate frames of the direct georeferencing unit and the 2D laser scanner. To this end, a calibration field is used, which consists of differently orientated georeferenced planar surfaces, leading to estimates for the lever arms and boresight angles with an accuracy of mm and one-tenth of a degree. Finally, point clouds of the mobile laser scanning system are compared with georeferenced point clouds of a high-precision 3D laser scanner. Accordingly, the accuracy of the system is in the order of cm to dm. This is in good agreement with the expected accuracy, which has been derived from the error propagation of previously estimated variance components. Numéro de notice : A2015--011 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1515/jag-2015-0011 En ligne : http://dx.doi.org/ 10.1515/jag-2015-0011 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80763
in Journal of applied geodesy > vol 9 n° 4 (December 2015) . - pp 227 - 243[article]PermalinkSlow feature analysis for change detection in multispectral imagery / Chen Wu in IEEE Transactions on geoscience and remote sensing, vol 52 n° 5 tome 1 (May 2014)PermalinkAutomated parameterisation for multi-scale image segmentation on multiple layers / L. Drăguț in ISPRS Journal of photogrammetry and remote sensing, vol 88 (February 2014)PermalinkAssessing the precision in loading estimates by geodetic techniques in Southern Europe / Pierre Valty in Geophysical journal international, vol 194 n° 3 (September 2013)PermalinkSupervised constrained optimization of Bayesian nonlocal means filter with sigma preselection for despeckling SAR images / Luis Gomez in IEEE Transactions on geoscience and remote sensing, vol 51 n° 8 (August 2013)PermalinkOn the formulation of the alternative hypothesis for geodetic outlier detection / Rüdiger Lehmann in Journal of geodesy, vol 87 n° 4 (April 2013)PermalinkFourier-series representation and projection of spherical harmonic functions / H. Cheong in Journal of geodesy, vol 86 n° 11 (November 2012)PermalinkAbleitung von Bewegungsstrategien zur automatisierten, vollständigen Vermessung von Innerraumszenen auf autonom navigierender Plattform / Alexander Fietz (2012)PermalinkPotentialities of multifrequency ionospheric correction in Global Navigation Satellite Systems / B. Kim in Journal of geodesy, vol 85 n° 3 (March 2011)PermalinkEfficient estimation of variance and covariance components : A case study for GPS stochastic model evaluation / B. Li in IEEE Transactions on geoscience and remote sensing, vol 49 n° 1 Tome 1 (January 2011)PermalinkApplying time-dependent variance-based global sensitivity analysis to represent the dynamics of an agent-based model of land use change / A. Ligmann-Zielinska in International journal of geographical information science IJGIS, vol 24 n°11-12 (december 2010)PermalinkThe combination of GNSS-levelling data and gravimetric (quasi-) geoid heights in the presence of noise / R. Klees in Journal of geodesy, vol 84 n° 12 (December 2010)PermalinkCombinaison linéaire et l'intérêt de la troisième fréquence pour le positionnement en double différence par GPS / L. Tabti in XYZ, n° 124 (septembre - novembre 2010)PermalinkAnalyse des séries temporelles SLR du géocentre et des EOP basées sur les mesures des satellites LAGEOS1/2 et Starlette / Bachir Gourine in Bulletin des sciences géographiques, n° 25 (juin 2010)PermalinkThe Forward Propagation of Integrated System Component Errors within Airborne Lidar Data / T. Goulden in Photogrammetric Engineering & Remote Sensing, PERS, vol 76 n° 5 (May 2010)PermalinkConstruction of spherical harmonic series for the potential derivatives of arbitrary orders in the geocentric Earth-fixed reference frame / M. Petrovskaya in Journal of geodesy, vol 84 n° 3 (March 2010)PermalinkIntroducing scale parameters for adjusting area objects in GIS based on least squares and variance component estimation / X. Tong in International journal of geographical information science IJGIS, vol 23 n°11-12 (november 2009)PermalinkImproved topographic correction of forest image data using a 3D canopy reflectance model in multiple forward mode / S.A. Soenen in International Journal of Remote Sensing IJRS, vol 29 n°3-4 (February 2008)PermalinkAide-mémoire de géostatistique linéaire / P. Chauvet (2008)PermalinkOptimizing image resolution to maximize the accuracy of hard classification / K.R. Mccloy in Photogrammetric Engineering & Remote Sensing, PERS, vol 73 n° 8 (August 2007)Permalink