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Laser scanning based growth analysis of plants as a new challenge for deformation monitoring / Jan Dupuis in Journal of applied geodesy, vol 10 n° 1 (March 2016)
[article]
Titre : Laser scanning based growth analysis of plants as a new challenge for deformation monitoring Type de document : Article/Communication Auteurs : Jan Dupuis, Auteur ; Christoph Holst, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2016 Article en page(s) : pp 37 - 44 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] B-Spline
[Termes IGN] croissance végétale
[Termes IGN] déformation géométrique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] feuille (végétation)
[Termes IGN] maillage par triangles
[Termes IGN] semis de points
[Termes IGN] tessellationRésumé : (auteur) Nowadays, the areal deformation analysis has become an important task in engineering geodesy. Thereby, not only manmade objects are of high interest, also natural objects, like plant organs, are focused more frequently. Thus, the analysis of leaf growth, i. e. the spatial development of the leaf surface, can be seen as a problem of deformation monitoring. In contrast to classical geodetic tasks, the absolute size of the deformation of the leaf surface is small, but usually great compared to the object size. Due to the optical characteristics of leaf surfaces, the point clouds, commonly acquired with high precision close-up laser scanners, provide a point-to-point distance that is small or equal compared to the measurement accuracy. Thus, the point clouds are usually processed and the leaf area is derived from a triangulation-based surface representation (mesh), resulting in a significant uncertainty of area calculation. In this paper, we illustrate the lacks of the mesh-based leaf area calculation. Using high precision gauge blocks as well as a number of tomato leaves, uncertainties of the area derivation are revealed and evaluated. The application of a B-spline approximation illustrates the advantages of an approximation-based approach and introduces the prospect for further research. Numéro de notice : A2016-552 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1515/jag-2015-0028 En ligne : http://dx.doi.org/10.1515/jag-2015-0028 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81698
in Journal of applied geodesy > vol 10 n° 1 (March 2016) . - pp 37 - 44[article]Potential of GPS common clock single-differences for deformation monitoring / Steffen Schön in Journal of applied geodesy, vol 10 n° 1 (March 2016)
[article]
Titre : Potential of GPS common clock single-differences for deformation monitoring Type de document : Article/Communication Auteurs : Steffen Schön, Auteur ; Hue Kiem Pham, Auteur ; Tobias Kersten, Auteur ; Julia Leute, Auteur ; Andreas Bauch, Auteur Année de publication : 2016 Article en page(s) : pp 45 - 52 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] déformation géométrique
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] horloge
[Termes IGN] positionnement cinématique
[Termes IGN] récepteur GNSS
[Termes IGN] simple différence
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) Global satellite navigation systems (GNSS) are a standard measurement device for deformation monitoring. In many applications, double-differences are used to reduce distance dependent systematic effects, as well as to eliminate the receiver and satellites clock errors. However, due to the navigation principle of one way ranging used in GPS, the geometry of the subsequent adjustment is weakened. As a result, the height component is generally determined three times less precisely than the horizontal coordinates. In addition, large correlations between the height and elevation dependent effects exist such as tropospheric refraction, mismodelled phase center variations, or multipath which restricts the attainable accuracy. However, for a kinematic analysis, i. e. for estimating high rate coordinate time series, the situation can be significantly improved if a common clock is connected to different GNSS receivers in a network or on a baseline. Consequently, between-station single-differences are sufficient to solve for the baseline coordinates. The positioning geometry is significantly improved which is reflected by a reduction of the standard deviation of kinematic heights by about a factor 3 underlining the benefits of this new approach. Real data from baselines at the Physikalisch-Technische Bundesanstalt campus at Braunschweig where receivers are connected over 290 m via an optical fiber link to a common clock was analysed. Numéro de notice : A2016-553 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2015-0029 En ligne : http://dx.doi.org/10.1515/jag-2015-0029 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81700
in Journal of applied geodesy > vol 10 n° 1 (March 2016) . - pp 45 - 52[article]Robust spatial approximation of laser scanner point clouds by means of Free-form Curve approaches in deformation analysis / Johannes Bureick in Journal of applied geodesy, vol 10 n° 1 (March 2016)
[article]
Titre : Robust spatial approximation of laser scanner point clouds by means of Free-form Curve approaches in deformation analysis Type de document : Article/Communication Auteurs : Johannes Bureick, Auteur ; Hamza Alkhatib, Auteur ; Ingo Neumann, Auteur Année de publication : 2016 Article en page(s) : pp 27 - 35 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] approximation
[Termes IGN] B-Spline
[Termes IGN] déformation géométrique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] estimation statistique
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] méthode robuste
[Termes IGN] semis de pointsRésumé : (auteur) In many geodetic engineering applications it is necessary to solve the problem of describing a measured data point cloud, measured, e. g. by laser scanner, by means of free-form curves or surfaces, e. g., with B-Splines as basis functions. The state of the art approaches to determine B-Splines yields results which are seriously manipulated by the occurrence of data gaps and outliers.
Optimal and robust B-Spline fitting depend, however, on optimal selection of the knot vector. Hence we combine in our approach Monte-Carlo methods and the location and curvature of the measured data in order to determine the knot vector of the B-Spline in such a way that no oscillating effects at the edges of data gaps occur. We introduce an optimized approach based on computed weights by means of resampling techniques. In order to minimize the effect of outliers, we apply robust M-estimators for the estimation of control points.
The above mentioned approach will be applied to a multi-sensor system based on kinematic terrestrial laserscanning in the field of rail track inspection.Numéro de notice : A2016-551 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1515/jag-2015-0020 En ligne : http://dx.doi.org/10.1515/jag-2015-0020 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81696
in Journal of applied geodesy > vol 10 n° 1 (March 2016) . - pp 27 - 35[article]Time series analysis of 3D coordinates using nonstochastic observations / Hiddo Velsink in Journal of applied geodesy, vol 10 n° 1 (March 2016)
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Titre : Time series analysis of 3D coordinates using nonstochastic observations Type de document : Article/Communication Auteurs : Hiddo Velsink, Auteur Année de publication : 2016 Article en page(s) : pp 5 - 16 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] compensation de coordonnées
[Termes IGN] coordonnées cartésiennes
[Termes IGN] déformation géométrique
[Termes IGN] matrice de covariance
[Termes IGN] série temporelle
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) Adjustment and testing of a combination of stochastic and nonstochastic observations is applied to the deformation analysis of a time series of 3D coordinates. Nonstochastic observations are constant values that are treated as if they were observations. They are used to formulate constraints on the unknown parameters of the adjustment problem. Thus they describe deformation patterns. If deformation is absent, the epochs of the time series are supposed to be related via affine, similarity or congruence transformations. S-basis invariant testing of deformation patterns is treated. The model is experimentally validated by showing the procedure for a point set of 3D coordinates, determined from total station measurements during five epochs. The modelling of two patterns, the movement of just one point in several epochs, and of several points, is shown. Full, rank deficient covariance matrices of the 3D coordinates, resulting from free network adjustments of the total station measurements of each epoch, are used in the analysis. Numéro de notice : A2016-549 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2015-0027 En ligne : http://dx.doi.org/10.1515/jag-2015-0027 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81693
in Journal of applied geodesy > vol 10 n° 1 (March 2016) . - pp 5 - 16[article]Correction de nuages de points lidar embarqué sur véhicule pour la reconstruction d’environnement 3D vaste / Pierre Merriaux (2016)
Titre : Correction de nuages de points lidar embarqué sur véhicule pour la reconstruction d’environnement 3D vaste Type de document : Article/Communication Auteurs : Pierre Merriaux, Auteur ; Y. Dupuis, Auteur ; R. Boutteau, Auteur ; Pascal Vasseur, Auteur ; X. Savatier, Auteur Editeur : Association française pour la reconnaissance et l'interprétation des formes AFRIF Année de publication : 2016 Conférence : RFIA 2016, 20e conférence Reconnaissance des Formes et Intelligence Artificielle 27/06/2016 01/07/2016 Clermond-Ferrand France OA Proceedings Importance : 6 p. Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] balayage laser
[Termes IGN] déformation géométrique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] instrument embarqué
[Termes IGN] lidar topographique
[Termes IGN] navigation autonome
[Termes IGN] vitesseRésumé : (auteur) Dans ces travaux, nous évaluons l’impact de différentes trajectoires de véhicule routier sur les nuages de points lidar embarqué. Effectivement, les fréquences de balayage des lidars sont faibles au regard des vitesses véhicule. Nous proposons une méthode pour palier ce problème et des métriques de comparaison. Nos résultats montrent qu’il est nécessaire de redresser les mesures de lidar embarqué avant de reconstruire en 3D des environnements vastes. Numéro de notice : C2016-018 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Communication DOI : sans En ligne : http://rfia2016.iut-auvergne.com/media/articles/JVI04.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84609 Documents numériques
en open access
Correction de nuages de points lidar embarquéAdobe Acrobat PDF Investigating efficacy of robust M-estimation of deformation from observation differences / Krzysztof Nowel in Survey review, vol 48 n° 346 (January 2016)PermalinkIdentification of movements using different geodetic methods of deformation analysis / Zoran Sušić in Geodetski vestnik, vol 59 n° 3 (September - November 2015)PermalinkEccentricity in images of circular and spherical targets and its impact on spatial intersection / Thomas Luhmann in Photogrammetric record, vol 29 n° 148 (December 2014 - February 2015)PermalinkChallenges in adapting example-based texture synthesis for panoramic map creation: a case study / Helen Jenny in Cartography and Geographic Information Science, vol 40 n° 4 (September 2013)PermalinkMesures de déformées initiales de poutres métalliques procédés topométriques au service d'essai statiques / V. Barras in XYZ, n° 133 (décembre 2012 - février 2013)PermalinkGraphical design of world map projections / Bernhard Jenny in International journal of geographical information science IJGIS, vol 24 n°11-12 (december 2010)PermalinkSome considerations on significance analysis for deformation detection via frequentist and Bayesian tests / F. Sacerdote in Journal of geodesy, vol 84 n° 4 (April 2010)PermalinkA discrete global grid system based on the parallels plane projection / T. Ma in International journal of geographical information science IJGIS, vol 23 n°9-10 (september 2009)PermalinkShape deformation in continuous map generalization / J. Danciger in Geoinformatica, vol 13 n° 2 (June 2009)PermalinkFlexion and skewness in map projections of the Earth / D. Goldberg in Cartographica, vol 42 n° 4 (December 2007)Permalink