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Termes IGN > 1- Outils - instruments et méthodes > instrument > instrument de mesure
instrument de mesureSynonyme(s)instrument de mesurage ;appareil de mesure appareil de mesurageVoir aussi |
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Analyzing the role of pulse density and voxelization parameters on full-waveform LiDAR-derived metrics / Pablo Crespo-Peremarch in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)
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Titre : Analyzing the role of pulse density and voxelization parameters on full-waveform LiDAR-derived metrics Type de document : Article/Communication Auteurs : Pablo Crespo-Peremarch, Auteur ; Luis Ángel Ruiz, Auteur ; Angel Balaguer-Beser, Auteur ; Javier Estornell, Auteur Année de publication : 2018 Article en page(s) : pp 453 - 464 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] Abies grandis
[Termes IGN] Acer macrophyllum
[Termes IGN] amplitude
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] étalonnage en vol
[Termes IGN] filtrage du bruit
[Termes IGN] forme d'onde pleine
[Termes IGN] impulsion laser
[Termes IGN] lidar à retour d'onde complète
[Termes IGN] Oregon (Etats-Unis)
[Termes IGN] prétraitement du signal
[Termes IGN] Pseudotsuga menziesii
[Termes IGN] Thuja plicata
[Termes IGN] Tsuga heterophylla
[Termes IGN] voxelRésumé : (auteur) LiDAR full-waveform (LFW) pulse density is not homogeneous along study areas due to overlap between contiguous flight stripes and, to a lesser extent, variations in height, velocity and altitude of the platform. As a result, LFW-derived metrics extracted at the same spot but at different pulse densities differ, which is called “side-lap effect”. Moreover, this effect is reflected in forest stand estimates, since they are predicted from LFW-derived metrics. This study was undertaken to analyze LFW-derived metric variations according to pulse density, voxel size and value assignation method in order to reduce the side-lap effect. Thirty LiDAR samples with a minimum density of 16 pulses.m−2 were selected from the testing area and randomly reduced to 2 pulses.m−2 with an interval of 1 pulse.m−2, then metrics were extracted and compared for each sample and pulse density at different voxel sizes and assignation values. Results show that LFW-derived metric variations as a function of pulse density follow a negative exponential model similar to the exponential semivariogram curve, increasing sharply until they reach a certain pulse density, where they become stable. This value represents the minimum pulse density (MPD) in the study area to optimally minimize the side-lap effect. This effect can also be reduced with pulse densities lower than the MPD modifying LFW parameters (i.e. voxel size and assignation value). Results show that LFW-derived metrics are not equally influenced by pulse density, such as number of peaks (NP) and ROUGHness of the outermost canopy (ROUGH) that may be discarded for further analyses at large voxel sizes, given that they are highly influenced by pulse density. In addition, side-lap effect can be reduced by either increasing pulse density or voxel size, or modifying the assignation value. In practice, this leads to a proper estimate of forest stand variables using LFW data. Numéro de notice : A2018-543 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2018.10.012 Date de publication en ligne : 05/11/2018 En ligne : https://doi.org/10.1016/j.isprsjprs.2018.10.012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91569
in ISPRS Journal of photogrammetry and remote sensing > vol 146 (December 2018) . - pp 453 - 464[article]Exemplaires(3)
Code-barres Cote Support Localisation Section Disponibilité 081-2018131 RAB Revue Centre de documentation En réserve L003 Disponible 081-2018133 DEP-EXM Revue LASTIG Dépôt en unité Exclu du prêt 081-2018132 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt Performance analysis of PPP positioning method by using IGS real-time service / Tatjana Kuzmić in Geodetski vestnik, vol 62 n° 4 (December 2018 - February 2019)
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Titre : Performance analysis of PPP positioning method by using IGS real-time service Type de document : Article/Communication Auteurs : Tatjana Kuzmić, Auteur ; Vladimir Bulatović, Auteur Année de publication : 2018 Article en page(s) : pp 604 - 618 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] horloge du récepteur
[Termes IGN] international GPS service for geodynamics
[Termes IGN] modèle mathématique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] retard troposphérique
[Termes IGN] Serbie
[Termes IGN] site web
[Termes IGN] temps de convergence
[Termes IGN] temps réel
[Termes IGN] test de performanceRésumé : (auteur) There are many positioning methods based on the usage of GNSS (Global Navigation Satellite System). They are classified according to the accuracy they can achieve, the time needed to obtain fixed solutions and the concept of positioning - number of used receivers, type of measurement, type of GNSS system, etc. One of the most important ways to do this is PPP (Precise Point Positioning) method, primarily because of its simplicity and cost-effectiveness. The paper describes PPP positioning method, its advantages and limitations, as well as the errors that can occur. It also provides an analysis of the performance of PPP method - precision, convergence time, loss of data reception, repeatability of positioning results and accuracy based on three measurement series in duration of 4 hours each, conducted on different days. By comparing the obtained coordinates with reference ones determined by AUSPOS web service, it can be concluded that the difference between these two sets of coordinates varies from 1 cm to 7 cm, while the accuracy of measured height is lower and the difference varies from 7 cm to 20 cm. Numéro de notice : A2019-014 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.15292/geodetski-vestnik.2018.04.604-618 Date de publication en ligne : 19/11/2018 En ligne : http://doi.org/10.15292/geodetski-vestnik.2018.04.604-618 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91618
in Geodetski vestnik > vol 62 n° 4 (December 2018 - February 2019) . - pp 604 - 618[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 139-2018041 RAB Revue Centre de documentation En réserve L003 Disponible Road safety evaluation through automatic extraction of road horizontal alignments from Mobile LiDAR System and inductive reasoning based on a decision tree / José Antonio Martin-Jimenez in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)
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Titre : Road safety evaluation through automatic extraction of road horizontal alignments from Mobile LiDAR System and inductive reasoning based on a decision tree Type de document : Article/Communication Auteurs : José Antonio Martin-Jimenez, Auteur ; Santiago Zazo, Auteur ; José Juan Arranz Justel, Auteur ; et al., Auteur Année de publication : 2018 Article en page(s) : pp 334 - 346 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] accident de la route
[Termes IGN] arbre de décision
[Termes IGN] cohérence géométrique
[Termes IGN] données GNSS
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] Espagne
[Termes IGN] extraction du réseau routier
[Termes IGN] indice de risque
[Termes IGN] lidar mobile
[Termes IGN] raisonnement
[Termes IGN] sécurité routière
[Termes IGN] segmentation
[Termes IGN] semis de points
[Termes IGN] triangulation de DelaunayRésumé : (auteur) Safe roads are a necessity for any society because of the high social costs of traffic accidents. This challenge is addressed by a novel methodology that allows us to evaluate road safety from Mobile LiDAR System data, taking advantage of the road alignment due to its influence on the accident rate. Automation is obtained through an inductive reasoning process based on a decision tree that provides a potential risk assessment. To achieve this, a 3D point cloud is classified by an iterative and incremental algorithm based on a 2.5D and 3D Delaunay triangulation, which apply different algorithms sequentially. Next, an automatic extraction process of road horizontal alignment parameters is developed to obtain geometric consistency indexes, based on a joint triple stability criterion. Likewise, this work aims to provide a powerful and effective preventive and/or predictive tool for road safety inspections. The proposed methodology was implemented on three stretches of Spanish roads, each with different traffic conditions that represent the most common road types. The developed methodology was successfully validated through as-built road projects, which were considered as “ground truth.” Numéro de notice : A2018-541 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2018.10.004 Date de publication en ligne : 21/10/2018 En ligne : https://doi.org/10.1016/j.isprsjprs.2018.10.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91565
in ISPRS Journal of photogrammetry and remote sensing > vol 146 (December 2018) . - pp 334 - 346[article]Exemplaires(3)
Code-barres Cote Support Localisation Section Disponibilité 081-2018131 RAB Revue Centre de documentation En réserve L003 Disponible 081-2018133 DEP-EXM Revue LASTIG Dépôt en unité Exclu du prêt 081-2018132 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt Estimation of satellite position, clock and phase bias corrections / Patrick Henkel in Journal of geodesy, vol 92 n° 10 (October 2018)
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Titre : Estimation of satellite position, clock and phase bias corrections Type de document : Article/Communication Auteurs : Patrick Henkel, Auteur ; Dimitrios Psychas, Auteur ; Christophe Günther, Auteur ; Urs Hugentobler, Auteur Année de publication : 2018 Article en page(s) : pp 1199 - 1217 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] ambiguïté entière
[Termes IGN] données Galileo
[Termes IGN] données GPS
[Termes IGN] double différence
[Termes IGN] erreur de phase
[Termes IGN] horloge atomique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] station de référenceRésumé : (Auteur) Precise point positioning with integer ambiguity resolution requires precise knowledge of satellite position, clock and phase bias corrections. In this paper, a method for the estimation of these parameters with a global network of reference stations is presented. The method processes uncombined and undifferenced measurements of an arbitrary number of frequencies such that the obtained satellite position, clock and bias corrections can be used for any type of differenced and/or combined measurements. We perform a clustering of reference stations. The clustering enables a common satellite visibility within each cluster and an efficient fixing of the double difference ambiguities within each cluster. Additionally, the double difference ambiguities between the reference stations of different clusters are fixed. We use an integer decorrelation for ambiguity fixing in dense global networks. The performance of the proposed method is analysed with both simulated Galileo measurements on E1 and E5a and real GPS measurements of the IGS network. We defined 16 clusters and obtained satellite position, clock and phase bias corrections with a precision of better than 2 cm. Numéro de notice : A2018-461 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1146-y Date de publication en ligne : 02/05/2018 En ligne : https://doi.org/10.1007/s00190-018-1146-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91060
in Journal of geodesy > vol 92 n° 10 (October 2018) . - pp 1199 - 1217[article]GPS satellite clock determination in case of inter-frequency clock biases for triple-frequency precise point positioning / Jiang Guo in Journal of geodesy, vol 92 n° 10 (October 2018)
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Titre : GPS satellite clock determination in case of inter-frequency clock biases for triple-frequency precise point positioning Type de document : Article/Communication Auteurs : Jiang Guo, Auteur ; Jianghui Geng, Auteur Année de publication : 2018 Article en page(s) : pp 1133 - 1142 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] erreur systématique
[Termes IGN] horloge atomique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] satellite GPSRésumé : (Auteur) Significant time-varying inter-frequency clock biases (IFCBs) within GPS observations prevent the application of the legacy L1/L2 ionosphere-free clock products on L5 signals. Conventional approaches overcoming this problem are to estimate L1/L5 ionosphere-free clocks in addition to their L1/L2 counterparts or to compute IFCBs between the L1/L2 and L1/L5 clocks which are later modeled through a harmonic analysis. In contrast, we start from the undifferenced uncombined GNSS model and propose an alternative approach where a second satellite clock parameter dedicated to the L5 signals is estimated along with the legacy L1/L2 clock. In this manner, we do not need to rely on the correlated L1/L2 and L1/L5 ionosphere-free observables which complicates triple-frequency GPS stochastic models, or account for the unfavorable time-varying hardware biases in undifferenced GPS functional models since they can be absorbed by the L5 clocks. An extra advantage over the ionosphere-free model is that external ionosphere constraints can potentially be introduced to improve PPP. With 27 days of triple-frequency GPS data from globally distributed stations, we find that the RMS of the positioning differences between our GPS model and all conventional models is below 1 mm for all east, north and up components, demonstrating the effectiveness of our model in addressing triple-frequency observations and time-varying IFCBs. Moreover, we can combine the L1/L2 and L5 clocks derived from our model to calculate precisely the L1/L5 clocks which in practice only depart from their legacy counterparts by less than 0.006 ns in RMS. Our triple-frequency GPS model proves convenient and efficient in combating time-varying IFCBs and can be generalized to more than three frequency signals for satellite clock determination. Numéro de notice : A2018-460 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-017-1106-y Date de publication en ligne : 28/12/2017 En ligne : https://doi.org/10.1007/s00190-017-1106-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91057
in Journal of geodesy > vol 92 n° 10 (October 2018) . - pp 1133 - 1142[article]Methods for quantification of systematic distance deviations under incidence angle with scanning total stations / Miriam Zámečníková in ISPRS Journal of photogrammetry and remote sensing, vol 144 (October 2018)
PermalinkPPPH : a MATLAB-based software for multi-GNSS precise point positioning analysis / Berkay Bahadur in GPS solutions, vol 22 n° 4 (October 2018)
PermalinkIn-situ measurements from mobile platforms: An emerging approach to address the old challenges associated with forest inventories / Xinlian Liang in ISPRS Journal of photogrammetry and remote sensing, vol 143 (September 2018)
PermalinkA quelles altitudes se trouvent les horloges atomiques de l'observatoire de Paris ? / Xavier Collilieux in XYZ, n° 156 (septembre - novembre 2018)
PermalinkOdometer, low-cost inertial sensors, and four-GNSS data to enhance PPP and attitude determination / Zhouzheng Gao in GPS solutions, vol 22 n° 3 (July 2018)
PermalinkData collection methods for forest inventory: a comparison between an integrated conventional equipment and terrestrial laser scanning / Bogdan Apostol in Annals of forest research, vol 61 n° 2 (July - December 2018)
PermalinkFinding timestamp offsets for a multi-sensor system using sensor observations / Raphael Voges in Photogrammetric Engineering & Remote Sensing, PERS, vol 84 n° 6 (juin 2018)
PermalinkLandmark based localization in urban environment / Xiaozhi Qu in ISPRS Journal of photogrammetry and remote sensing, vol 140 (June 2018)
PermalinkArpent : un prototype de haute exactitude pour les mesures de grande distance / Maylis Teyssendier de la Serve in XYZ, n° 154 (mars - mai 2018)
PermalinkComparing nearest neighbor configurations in the prediction of species-specific diameter distributions / Janne Raty in Annals of Forest Science, vol 75 n° 1 (March 2018)
PermalinkHigh performance clocks and gravity field determination / Jurgen Müller in Space Science Reviews, vol 214 n° 1 (February 2018)
PermalinkCartographie des déformations de surface sur l’île de Taiwan par interférométrie RADAR Sentinel-1 / Miloud Fekaouni (2018)
PermalinkPermalinkDétermination du géopotentiel à haute résolution spatiale : apport des horloges atomiques et des algorithmes génétiques / Guillaume Lion (2018)
PermalinkDétermination d’un modèle géopotentiel à haute résolution en zone littorale aidé par des mesures d’horloges atomiques / Hugo Lecomte (2018)
PermalinkPermalinkSuivi des impacts d’un arasement de barrage sur la végétation riveraine par télédétection à très haute résolution spatiale et temporelle / Marianne Laslier (2018)
PermalinkTERRISCOPE, une nouvelle plateforme mutualisée de recherche en télédétection optique à partir d’avions et de drones / Yannick Boucher (2018)
PermalinkThe effect of regional sea level atmospheric pressure on sea level variations at globally distributed tide gauge stations with long records / Huseyin Baki Iz in Journal of geodetic science, vol 8 n° 1 (January 2018)
PermalinkTight integration of INS/Stereo VO/Digital map for land vehicle navigation / Fei Liu in Photogrammetric Engineering & Remote Sensing, PERS, vol 84 n° 1 (January 2018)
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