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Measuring wood density by means of X-ray computer tomography / Charline Freyburger in Annals of Forest Science, Vol 66 n° 8 (December 2009)
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Titre : Measuring wood density by means of X-ray computer tomography Titre original : Mesure de la densité du bois par tomographie à rayons X Type de document : Article/Communication Auteurs : Charline Freyburger, Auteur ; Fleur Longuetaud, Auteur ; Frédéric Mothe, Auteur ; Thiéry Constant, Auteur ; Jean-Michel Leban , Auteur
Année de publication : 2009 Article en page(s) : n° 804 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] biomasse
[Termes IGN] densité du bois
[Termes IGN] étalonnage d'instrument
[Termes IGN] puits de carbone
[Termes IGN] rayon X
[Termes IGN] tomographieRésumé : (Auteur) Wood density is a characteristic of major interest. Usually, it is used as an indicator of wood quality; however, in the context of global change, it is increasingly used for biomass and carbon storage estimations. X-ray computer tomography is a method which enables quick estimates of wood density after applying a calibration procedure.
A review of the literature is presented in this article. Most of the previous studies have been performed in the 80’s or at the beginning of the 90’s. In this study, the relationship between wood density and Hounsfield numbers was investigated using a recent medical scanner. A linear relationship was fitted using a calibration data set which consisted in tropical wood samples representing a large range of densities ranging between 133 and 1319 kg m−3, and then validated using an independent data set (mainly temperate tree species). The fitted relationships were very strong (R2 > 0.999), whichever the tested scanner settings, with slight but significant effects of the current voltage and reconstruction filters. The RMSE values computed from the validation data set ranged between 5.4 and 7.7 kg m−3 for densities ranging between 364 and 821 kg m−3. In conclusion, this method of calibration enables the use of a medical scanner to obtain maps of wood density, in a fast and non destructive way, and with a very good accuracy. Very interesting perspectives are opened regarding biomass distribution within trees.Numéro de notice : A2009-610 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1051/forest/2009071 Date de publication en ligne : 25/11/2009 En ligne : https://www.afs-journal.org/articles/forest/full_html/2009/08/f09029/f09029.html Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=72893
in Annals of Forest Science > Vol 66 n° 8 (December 2009) . - n° 804[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité IFN-001-P000694 PER Revue Nogent-sur-Vernisson Salle périodiques Exclu du prêt The building shadow problem of airborne lidar / T.Y. Shih in Photogrammetric record, vol 24 n° 128 (December 2009 - February 2010)
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Titre : The building shadow problem of airborne lidar Type de document : Article/Communication Auteurs : T.Y. Shih, Auteur ; C. Huang, Auteur Année de publication : 2009 Article en page(s) : pp 372 - 385 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] champ visuel
[Termes IGN] données lidar
[Termes IGN] modèle numérique de surface
[Termes IGN] ombre
[Termes IGN] plan de vol
[Termes IGN] semis de points
[Termes IGN] télémétrie laser aéroportéRésumé : (Auteur) Airborne lidar systems are equipped with a scanning mechanism that produces a swath of 3D coordinated points to form a cloud in each flight strip. The scanning is perpendicular to the direction of flight. The density of the point cloud is one of the major quality measures for the data collected with such systems. Point density, shade (occlusion of the laser beam) and penetration rate are major factors to be considered in the flight design. For practical operations, flight missions may be designed with overlaps ranging from 5 to 50%. Aside from the percentage overlap, the field of view is another important parameter for flight design. An evaluation scheme to assess the percentage overlap between flight strips and the selection of the field of view is proposed in this study. The influences of overlap and field of view are also demonstrated with real data gathered by an airborne lidar system. Copyright RS&PS + Blackwell Publishing Numéro de notice : A2009-498 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2009.00550.x En ligne : https://doi.org/10.1111/j.1477-9730.2009.00550.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30127
in Photogrammetric record > vol 24 n° 128 (December 2009 - February 2010) . - pp 372 - 385[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 106-09041 RAB Revue Centre de documentation En réserve L003 Disponible
Titre : Lidar waveform modeling using a marked point process Type de document : Article/Communication Auteurs : Clément Mallet , Auteur ; Florent Lafarge, Auteur ; Uwe Soergel, Auteur ; Christian Heipke, Auteur ; Frédéric Bretar, Auteur
Editeur : New York : Institute of Electrical and Electronics Engineers IEEE Année de publication : 07/11/2009 Conférence : ICIP 2009, 16th IEEE International Conference on Image Processing 07/11/2009 10/11/2009 Le Caire Egypte Proceedings IEEE Importance : 4 p. Format : 21 x 30 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] algorithme du recuit simulé
[Termes IGN] chaîne de Markov
[Termes IGN] données localisées 3D
[Termes IGN] forme d'onde
[Termes IGN] lasergrammétrie
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] milieu urbain
[Termes IGN] processus ponctuel marqué
[Termes IGN] reconstruction du signal
[Termes IGN] semis de points
[Termes IGN] signal laser
[Termes IGN] signal lidarRésumé : (Auteur) Lidar waveforms are 1D signal consisting of a train of echoes where each of them correspond to a scattering target of the Earth surface. Modeling these echoes with the appropriate parametric function is necessary to retrieve physical information about these objects and characterize their properties. This paper presents a marked point process based model to reconstruct a lidar signal in terms of a set of parametric functions. The model takes into account both a data term which measures the coherence between the models and the waveforms, and a regularizing term which introduces physical knowledge on the reconstructed signal. We search for the best configuration of functions by performing a Reversible Jump Markov Chain Monte Carlo sampler coupled with a simulated annealing. Results are finally presented on different kinds of signals in urban areas. Numéro de notice : C2009-048 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE/POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1109/ICIP.2009.5413380 En ligne : https://doi.org/10.1109/ICIP.2009.5413380 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64296 Documents numériques
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Lidar waveform modeling ... - pdf auteurAdobe Acrobat PDFImproving the GNSS positioning stochastic model in the presence of ionospheric scintillation / M. Aquino in Journal of geodesy, vol 83 n° 10 (October 2009)
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Titre : Improving the GNSS positioning stochastic model in the presence of ionospheric scintillation Type de document : Article/Communication Auteurs : M. Aquino, Auteur ; João F.G. Monico, Auteur ; A.H. Dodson, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 953 - 966 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] modèle stochastique
[Termes IGN] positionnement par GNSS
[Termes IGN] propagation ionosphérique
[Termes IGN] récepteur GNSS
[Termes IGN] scintillation
[Termes IGN] teneur totale en électronsRésumé : (Auteur) Ionospheric scintillations are caused by time- varying electron density irregularities in the ionosphere, occurring more often at equatorial and high latitudes. This paper focuses exclusively on experiments undertaken in Europe, at geographic latitudes between ~50°N and ~80°N, where a network of GPS receivers capable of monitoring Total Electron Content and ionospheric scintillation parameters was deployed. The widely used ionospheric scintillation indices S4 and {\sigma_{\varphi}} represent a practical measure of the intensity of amplitude and phase scintillation affecting GNSS receivers. However, they do not provide sufficient information regarding the actual tracking errors that degrade GNSS receiver performance. Suitable receiver tracking models, sensitive to ionospheric scintillation, allow the computation of the variance of the output error of the receiver PLL (Phase Locked Loop) and DLL (Delay Locked Loop), which expresses the quality of the range measurements used by the receiver to calculate user position. The ability of such models of incorporating phase and amplitude scintillation effects into the variance of these tracking errors underpins our proposed method of applying relative weights to measurements from different satellites. That gives the least squares stochastic model used for position computation a more realistic representation, vis-a-vis the otherwise ‘equal weights’ model. For pseudorange processing, relative weights were com- puted, so that a ‘scintillation-mitigated’ solution could be performed and compared to the (non-mitigated) ‘equal weights’ solution. An improvement between 17 and 38% in height accuracy was achieved when an epoch by epoch differential solution was computed over baselines ranging from 1 to 750 km. The method was then compared with alternative approaches that can be used to improve the least squares stochastic model such as weighting according to satellite elevation angle and by the inverse of the square of the standard deviation of the code/carrier divergence (sigma CCDiv). The influence of multipath effects on the proposed mitigation approach is also discussed. With the use of high rate scintillation data in addition to the scintillation indices a carrier phase based mitigated solution was also implemented and compared with the conventional solution. During a period of occurrence of high phase scintillation it was observed that problems related to ambiguity resolution can be reduced by the use of the proposed mitigated solution. Copyright Springer Numéro de notice : A2009-430 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-009-0313-6 En ligne : https://doi.org/10.1007/s00190-009-0313-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30061
in Journal of geodesy > vol 83 n° 10 (October 2009) . - pp 953 - 966[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09091 SL Revue Centre de documentation Revues en salle Disponible Classification comparisons between dual-pol, compact polarimetric and quad-pol SAR imagery / T. Ainsworth in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 5 (September - October 2009)
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Titre : Classification comparisons between dual-pol, compact polarimetric and quad-pol SAR imagery Type de document : Article/Communication Auteurs : T. Ainsworth, Auteur ; J. Kelly, Auteur ; J. Lee, Auteur Année de publication : 2009 Article en page(s) : pp 464 - 471 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] analyse comparative
[Termes IGN] classification dirigée
[Termes IGN] image radar moirée
[Termes IGN] modèle de rétrodiffusion
[Termes IGN] polarimétrie radar
[Termes IGN] polarisation
[Termes IGN] polarisation croisée
[Termes IGN] précision de la classificationRésumé : (Auteur) We present a study of the polarimetric information content of dual-pol imaging modes and dual-pol imaging extended by polarimetric scattering models. We compare Wishart classifications both among the partial polarimetric datasets and against the full quad-pol dataset. Our emphasis is the inter-comparisons between the classification results based on dual-pol modes, compact polarimetric modes and scattering model extensions of the compact polarimetric modes. We primarily consider novel dual-pol modes, e.g. transmitting a circular polarization and receiving horizontal and vertical polarizations, and the pseudo-quad-pol data derived from polarimetric scattering models based on dual-pol data. We show that the overall classification accuracy of the pseudo-quad-pol data is essential the same as the classification accuracy obtained directly employing the underlying dual-pol imagery.We present a study of the polarimetric information content of dual-pol imaging modes and dual-pol imaging extended by polarimetric scattering models. We compare Wishart classifications both among the partial polarimetric datasets and against the full quad-pol dataset. Our emphasis is the inter-comparisons between the classification results based on dual-pol modes, compact polarimetric modes and scattering model extensions of the compact polarimetric modes. We primarily consider novel dual-pol modes, e.g. transmitting a circular polarization and receiving horizontal and vertical polarizations, and the pseudo-quad-pol data derived from polarimetric scattering models based on dual-pol data. We show that the overall classification accuracy of the pseudo-quad-pol data is essential the same as the classification accuracy obtained directly employing the underlying dual-pol imagery. Copyright ISPRS Numéro de notice : A2009-399 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2008.12.008 En ligne : https://doi.org/10.1016/j.isprsjprs.2008.12.008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30030
in ISPRS Journal of photogrammetry and remote sensing > vol 64 n° 5 (September - October 2009) . - pp 464 - 471[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-09051 SL Revue Centre de documentation Revues en salle Disponible Digital airborne photogrammetry - a new tool for quantitative remote sensing? - a state-of-the-art review on radiometric aspects of digital photogrammetric images / Eija Honkavaara in Remote sensing, vol 1 n° 3 (September 2009)
PermalinkDiscrimination of agricultural crops in a tropical semi-arid region of Brazil based on L-band polarimetric airborne SAR data / W. Silva in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 5 (September - October 2009)
PermalinkInterferometric SAR for characterization of ravines as a function of their density, depth, and surface cover / R.S. Chatterjee in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 5 (September - October 2009)
PermalinkInvestigating tropospheric effects and seasonal position variations in GPS and DORIS time-series from the Nepal Himalaya / Mireille Flouzat in Geophysical journal international, vol 178 n° 3 (September 2009)
PermalinkRemote sensing of the outgoing surface infrared-radiation of regional faults and its geophysical indicators / N. Vilor in Photo interprétation, European journal of applied remote sensing, vol 45 n° 3 (septembre 2009)
PermalinkRemote sensing with reflected signals: GNSS-R data processing software and test analysis / D. Yang in Inside GNSS, vol 4 n° 5 (September - October 2009)
PermalinkArchitecture for a future C-band/L-band GNSS mission : Part 2 signal considerations and related user terminal aspects / José Avila-Rodriguez in Inside GNSS, vol 4 n° 4 (July - August 2009)
PermalinkA comparative analysis of DEM-based models to estimate the solar radiation in mountainous terrain / J. Ruiz-Arias in International journal of geographical information science IJGIS, vol 23 n° 7-8 (july 2009)
PermalinkMaking sense of inter-signal corrections: accounting for GPS satellite calibration parameters in legacy and modernized ionosphere correction algorithms / Avram Tetewsky in Inside GNSS, vol 4 n° 4 (July - August 2009)
PermalinkUse Markov random fields for automatic cloud-shadow detection on high resolution / Sylvie Le Hégarat-Mascle in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 4 (July - August 2009)
PermalinkAssessing image processing techniques for geological mapping: a case study in Eljufra, Libya / N.M. Saadi in Geocarto international, vol 24 n° 3 (June - July 2009)
PermalinkHigh-sensitivity GPS: an availability, reliability and accuracy test / V. Schweiger in Bulletin des sciences géographiques, n° 23 (juin 2009)
PermalinkInfluence of macroscale and microscale surface roughness on multi-beam RADARSAT-1 data: implications for geological mapping in the Curaçá Valley, Brazil / W.R. Paradella in Photo interprétation, European journal of applied remote sensing, vol 45 n° 2 (juin 2009)
PermalinkPotentiality of feed-forward neural networks for classifying dark formations to oil spills and look-alikes / Konstantinos Topouzelis in Geocarto international, vol 24 n° 3 (June - July 2009)
PermalinkThe application of Advanced Space-Borne Thermal Emission and Reflection (ASTER) radiometer data in the detection of alteration paleocrater, Bafq region, central Iran / A. Moghtaderi in Photo interprétation, European journal of applied remote sensing, vol 45 n° 2 (juin 2009)
PermalinkArchitecture for a future C-band/L-band GNSS mission: Part 1 C-band services, space- and ground segment, overall performance / A. Schmitz-Peiffer in Inside GNSS, vol 4 n° 3 (May - June 2009)
PermalinkPan-European forest/non forest mapping with Landsat ETM+ and Corine Land Cover 2000 data / A. Pekkarinen in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 2 (March - April 2009)
PermalinkRadiometric Calibration of LIDAR Intensity With Commercially Available Reference Targets / S. Kaasalainen in IEEE Transactions on geoscience and remote sensing, vol 47 n° 2 (February 2009)
PermalinkUsing ENVISAT ASAR global mode data for surface soil moisture retrieval over Oklahoma, USA / Carsten Pathe in IEEE Transactions on geoscience and remote sensing, vol 47 n° 2 (February 2009)
PermalinkApport des mesures directionnelles et polarisées aux corrections atmosphériques au-dessus des océans ouverts. Application à la mission PARASOL / Tristan Harmel (2009)
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