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Effects of topographic variability and Lidar sampling density on several DEM interpolation methods / Q. Guo in Photogrammetric Engineering & Remote Sensing, PERS, vol 76 n° 6 (June 2010)
[article]
Titre : Effects of topographic variability and Lidar sampling density on several DEM interpolation methods Type de document : Article/Communication Auteurs : Q. Guo, Auteur ; W. Li, Auteur ; H. Yu, Auteur ; O. Alvarez, Auteur Année de publication : 2010 Article en page(s) : pp 701 - 712 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] classification barycentrique
[Termes IGN] densité des points
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] fonction spline d'interpolation
[Termes IGN] interpolation
[Termes IGN] interpolation inversement proportionnelle à la distance
[Termes IGN] krigeage
[Termes IGN] modèle numérique de terrain
[Termes IGN] Triangulated Irregular Network
[Termes IGN] variabilitéRésumé : (Auteur) This study aims to quantify the effects of topographic variability (measured by coefficient variation of elevation, CV) and lidar (Light Detection and Ranging) sampling density on the DEM (Digital Elevation Model) accuracy derived from several interpolation methods at different spatial resolutions. Interpolation methods include natural neighbor (NN), inverse distance weighted (IDW), triangulated irregular network (TIN), spline, ordinary kriging (OK), and universal kriging (UK). This study is unique in that a comprehensive evaluation of the combined effects of three influencing factors (CV, sampling density, and spatial resolution) on lidar-derived DEM accuracy is carried out using different interpolation methods. Results indicate that simple interpolation methods, such as IDW, NN, and TIN, are more efficient at generating DEMs from lidar data, but kriging-based methods, such as OK and UK, are more reliable if accuracy is the most important consideration. Moreover, spatial resolution also plays an important role when generating DEMs from lidar data. Our results could be used to guide the choice of appropriate lidar interpolation methods for DEM generation given the resolution, sampling density, and topographic variability. Numéro de notice : A2010-228 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.76.6.701 En ligne : https://doi.org/10.14358/PERS.76.6.701 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30422
in Photogrammetric Engineering & Remote Sensing, PERS > vol 76 n° 6 (June 2010) . - pp 701 - 712[article]Obtaining high fidelity triangular Regular Network from only DEM points / T. Gökgöz in Cartographic journal (the), vol 47 n° 2 (May 2010)
[article]
Titre : Obtaining high fidelity triangular Regular Network from only DEM points Type de document : Article/Communication Auteurs : T. Gökgöz, Auteur Année de publication : 2010 Article en page(s) : pp 150 - 156 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] contour
[Termes IGN] interpolation
[Termes IGN] modèle numérique de surface
[Termes IGN] pente
[Termes IGN] tessellation
[Termes IGN] Triangular Regular Network
[Termes IGN] triangulation (topologie)Résumé : (Auteur) When the source data for the digital elevation model (DEM) are not known and any additional information or features such as skeleton lines of terrain is not available, a triangular regular network (TRN) is constructed with simple subdivision using one or two diagonals uniformly. Such a model gives inaccurate directions for interpolation because of the inaccurate diagonals used in triangulation and thereby, results in inaccurate contours representing artificial terrain features. In this study, a new method is developed based on slope information computed at DEM points determining accurate diagonals in the subdivision process, which is beneficial not only through the skeleton lines of a terrain but also all over the DEM. Consequently, it is shown that the proposed method is able to build a high fidelity TRN from a DEM without any additional information or features. Copyright British Cartographic Society Numéro de notice : A2010-260 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/000870409X12584524219009 Date de publication en ligne : 18/07/2013 En ligne : https://doi.org/10.1179/000870409X12584524219009 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30454
in Cartographic journal (the) > vol 47 n° 2 (May 2010) . - pp 150 - 156[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 030-2010021 RAB Revue Centre de documentation En réserve L003 Disponible Using landscape characteristics to define an adjusted distance metric for improving kriging interpolations / S. Lyon in International journal of geographical information science IJGIS, vol 24 n° 5-6 (may 2010)
[article]
Titre : Using landscape characteristics to define an adjusted distance metric for improving kriging interpolations Type de document : Article/Communication Auteurs : S. Lyon, Auteur ; R. Sorensen, Auteur ; J. Stendahl, Auteur ; J. Seibert, Auteur Année de publication : 2010 Article en page(s) : pp 723 - 740 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] azote
[Termes IGN] carbone
[Termes IGN] distance euclidienne
[Termes IGN] humidité du sol
[Termes IGN] interpolation
[Termes IGN] krigeage
[Termes IGN] métrique
[Termes IGN] Suède
[Termes IGN] variogrammeRésumé : (Auteur) Interpolation of point measurements using geostatistical techniques such as kriging can be used to estimate values at non-sampled locations in space. Traditional geostatistics are based on the spatial autocorrelation concept that nearby things are more related than distant things. In this study, additional information was used to modify the traditional Euclidean concept of distance into an adjusted distance metric that incorporates similarity in terms of quantifiable landscape characteristics such as topography or land use. This new approach was tested by interpolating soil moisture content, pH and carbon-to-nitrogen (C:N) ratio measured in both the mineral and the organic soil layers at a field site in central Sweden. Semivariograms were created using both the traditional distance metrics and the proposed adjusted distance metrics to carry out ordinary kriging (OK) interpolations between sampling points. In addition, kriging with external drift (KED) was used to interpolate soil properties to evaluate the ability of the adjusted distance metric to incorporate secondary data into interpolations. The new adjusted distance metric typically lowered the nugget associated with the semivariogram, thereby better representing small-scale variability in the measured data compared to semivariograms based on the traditional distance metric. The pattern of the resulting kriging interpolations using KED and OK based on the adjusted distance metric were similar because they represented secondary data and, thus, enhanced small-scale variability compared to traditional distance OK. This created interpolations that agreed better with what is expected for the real-world spatial variation of the measured properties. Based on cross-validation error, OK interpolations using the adjusted distance metric better fit observed data than either OK interpolations using traditional distance or KED. Copyright Taylor & Francis Numéro de notice : A2010-168 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Article DOI : 10.1080/13658810903062487 En ligne : https://doi.org/10.1080/13658810903062487 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30363
in International journal of geographical information science IJGIS > vol 24 n° 5-6 (may 2010) . - pp 723 - 740[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-2010032 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010031 RAB Revue Centre de documentation En réserve L003 Disponible Visualisation of origins, destinations and flows with OD maps / J. Wood in Cartographic journal (the), vol 47 n° 2 (May 2010)
[article]
Titre : Visualisation of origins, destinations and flows with OD maps Type de document : Article/Communication Auteurs : J. Wood, Auteur ; A. Slingsby, Auteur ; Jason Dykes, Auteur Année de publication : 2010 Article en page(s) : pp 117 - 129 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] arc
[Termes IGN] cartographie des flux
[Termes IGN] cartographie dynamique
[Termes IGN] généralisation cartographique automatisée
[Termes IGN] matrice
[Termes IGN] migration humaine
[Termes IGN] trajectographie (positionnement)
[Termes IGN] visualisation cartographique
[Termes IGN] visualisation de donnéesRésumé : (Auteur) We present a new technique for the visual exploration of origins (O) and destinations (D) arranged in geographic space. Previous attempts to map the flows between origins and destinations have suffered from problems of occlusion usually requiring some form of generalisation, such as aggregation or flow density estimation before they can be visualized. This can lead to loss of detail or the introduction of arbitrary artefacts in the visual representation. Here, we propose mapping OD vectors as cells rather than lines, comparable with the process of constructing OD matrices, but unlike the OD matrix, we preserve the spatial layout of all origin and destination locations by constructing a gridded two-level spatial treemap. The result is a set of spatially ordered small multiples upon which any arbitrary geographic data may be projected. Using a hash grid spatial data structure, we explore the characteristics of the technique through a software prototype that allows interactive query and visualisation of 105-106 simulated and recorded OD vectors. The technique is illustrated using US county to county migration and commuting statistics. Copyright British Cartographic Society Numéro de notice : A2010-258 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/000870410X12658023467367 Date de publication en ligne : 18/07/2013 En ligne : https://doi.org/10.1179/000870410X12658023467367 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30452
in Cartographic journal (the) > vol 47 n° 2 (May 2010) . - pp 117 - 129[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 030-2010021 RAB Revue Centre de documentation En réserve L003 Disponible Impact of regional reference frame definition on geodynamic interpretations / Juliette Legrand in Journal of geodynamics, vol 49 n° 3-4 (April 2010)
[article]
Titre : Impact of regional reference frame definition on geodynamic interpretations Type de document : Article/Communication Auteurs : Juliette Legrand, Auteur ; Nicolas Bergeot, Auteur ; Carine Bruyninx, Auteur ; Guy Wöppelmann , Auteur ; Marie-Noëlle Bouin , Auteur ; Zuheir Altamimi , Auteur Année de publication : 2010 Article en page(s) : pp 116 - 122 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] champ de vitesse
[Termes IGN] données GNSS
[Termes IGN] Europe (géographie physique)
[Termes IGN] géodynamique
[Termes IGN] International Terrestrial Reference FrameRésumé : (auteur) Ten years (1997–2006) of weekly GNSS solutions of 205 globally distributed stations have been used to investigate the impact of the reference frame definition on the estimated station velocities. For that purpose, weekly regional solutions (covering the European region) and global solutions have been, respectively, stacked to obtain regional and global velocity fields. In both cases, the estimated long-term solutions (station positions and velocities) were tied to the ITRF2005 under minimal constraints using a selected set of reference stations. Several sets of global and regional reference stations were tested to evaluate first the impact of the reference frame definition on the global and regional velocity fields and later the impact on the derived geodynamic interpretations.
Results confirm that the regional velocity fields show systematic effects with respect to the global velocity field with differences reaching up to 1.3 mm/year in the horizontal and 2.9 mm/year in the vertical depending on the geographical extent of the network and the chosen set of regional reference stations.
In addition, the estimations of the Euler pole for Western Europe differ significantly when considering a global or a regional strategy. After removing the rigid block rotation, the residual velocity fields show differences which can reach up to 0.8 mm/year in horizontal component.
In Northern Europe, the vertical ground motion is dominated by the Glacial Isostatic Adjustment (GIA). A proper modeling of this effect requires sub-mm/year precision for the vertical velocities for latitudes below 56°. We demonstrate that a profile of vertical velocities shows significant discrepancies according to the reference frame definition strategy. In the case of regional solutions, the vertical modeling does not predict any subsidence around 52° as predicted by the global solution and previous studies.
In summary, we evidence the limitation of regional networks to reconstruct absolute velocity fields and conclude that when geodynamics require the highest precisions for the GNSS-based velocities, a global reference frame definition is more reliable.Numéro de notice : A2010-638 Affiliation des auteurs : IGN+Ext (1940-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.jog.2009.10.002 Date de publication en ligne : 14/10/2009 En ligne : https://doi.org/10.1016/j.jog.2009.10.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89892
in Journal of geodynamics > vol 49 n° 3-4 (April 2010) . - pp 116 - 122[article]Construction 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)PermalinkDetecting negative spatial autocorrelation in georeferenced random variables / Daniel A. Griffith in International journal of geographical information science IJGIS, vol 24 n°3-4 (march 2010)PermalinkNetwork adjustment in surveying engineering: linear goal programming versus least squares / S. Alp in SaLIS Surveying and land information science, vol 70 n° 1 (Spring 2010)PermalinkOptimization of mobile radioactivity monitoring networks / Gerard B.M. Heuvelink in International journal of geographical information science IJGIS, vol 24 n°3-4 (march 2010)PermalinkPrediction of vertical deflections from high-degree spherical harmonic synthesis and residual terrain model data / C. Hirt in Journal of geodesy, vol 84 n° 3 (March 2010)PermalinkThe future of aerial archaeology in Europe / W.S. Hanson in Photo interprétation, European journal of applied remote sensing, vol 46 n° 1 (mars 2010)PermalinkFinite element method for solving geodetic boundary value problems / Z. Faskova in Journal of geodesy, vol 84 n° 2 (February 2010)PermalinkGeospatial database organization and spatial decision analysis for biodiversity databases in web GIS environment / Harish Chandra Karnatak in Geocarto international, vol 25 n° 1 (February 2010)PermalinkGrid-enabling Geographically Weighted Regression: a case study of participation in higher education in England / R. Harris in Transactions in GIS, vol 14 n° 1 (February 2010)PermalinkAssessment of a numerical method for computing the spherical harmonic coefficients of the gravitational potential of a constant density polyhedron / Olivier Jamet (2010)PermalinkDétection d'empreintes de bâtiments dans un modèle numérique d'élévation : une approche énergétique / Olivier Tournaire (2010)PermalinkEstimation of digitizing and polygonal approximation errors in the computation of length in vector databases / Jean-François Girres (2010)PermalinkGlobal optimization of core station networks for space geodesy: application to the referencing of the SLR EOP with respect to ITRF / David Coulot in Journal of geodesy, vol 84 n° 1 (January 2010)PermalinkMathématiques pour le traitement du signal / M. Bergounioux (2010)PermalinkMéthodologie GPS, mesure des déformations verticales et humidité atmosphérique / Marie-Noëlle Bouin (2010)PermalinkModelling three-dimensional geoscientific datasets with the discrete Voronoi diagram / T. Van Der Putte (2010)PermalinkModelling vertical error in LiDAR-derived digital elevation models / F. Aguilar in ISPRS Journal of photogrammetry and remote sensing, vol 65 n° 1 (January - February 2010)PermalinkSpatial interpolation in wireless sensor networks: localized algorithms for variogram modeling and kriging / M. Umer in Geoinformatica, vol 14 n° 1 (January 2010)PermalinkTransformation of amplitudes and frequencies of precession and nutation of the earth’s rotation vector to amplitudes and frequencies of diurnal polar motion / Bernd Richter in Journal of geodesy, vol 84 n° 1 (January 2010)PermalinkAutomated processing for map generation using web services / Moritz Neun in Geoinformatica, vol 13 n° 4 (December 2009)Permalink