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Precise reflectorless distance measurement: advance focusing optics for laser distance measurement / H. Kishimoto in GIM international, vol 15 n° 9 (September 2001)
[article]
Titre : Precise reflectorless distance measurement: advance focusing optics for laser distance measurement Type de document : Article/Communication Auteurs : H. Kishimoto, Auteur Année de publication : 2001 Article en page(s) : pp 47 - 49 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Métrologie
[Termes IGN] laser
[Termes IGN] optique
[Termes IGN] réflexion (rayonnement)
[Termes IGN] télémétrie laserRésumé : (Auteur) Reflectorless distance measurement (RML) has over the recent past become common in surveying. Here, what is being measured is important and should be considered more carefully than traditional ways distance measurement. A focusing optical system was designed to adapt RML to surveying requirements. RML also has potential for new applications by user-designed tergets. The author presents characteristics of RLM and considerations for the design of provisional and application-oriented tergets. Numéro de notice : A2001-067 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21767
in GIM international > vol 15 n° 9 (September 2001) . - pp 47 - 49[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 061-01091 RAB Revue Centre de documentation En réserve L003 Disponible Atmospheric modeling in GPS data analysis for high accuracy positioning / Olivier Bock in Physics and chemistry of the Earth, Part A: Solid Earth and Geodesy, vol 26 n° 6-8 (2001)
[article]
Titre : Atmospheric modeling in GPS data analysis for high accuracy positioning Type de document : Article/Communication Auteurs : Olivier Bock , Auteur ; Erik Doerflinger, Auteur Année de publication : 2001 Article en page(s) : pp 373 - 383 Note générale : biblographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] données GPS
[Termes IGN] modèle atmosphérique
[Termes IGN] retard troposphérique zénithalRésumé : (auteur) In this paper we review the atmospheric modeling methods used in GPS data analysis. Due to the strong spatial inhomogeneity and temporal variability of atmospheric constituents, especially water vapor, accurate modeling of path delay in GPS signals is necessary for high-accuracy positioning (e.g., tectonics and sea-level change) and meteorological applications (climatology and weather forecasting). State-of-the-art path delay modeling consists primarily in parameter estimation. In this strategy, zenith path delays are estimated during the GPS data reduction. External correction is another common strategy, in which the wet path delay is measured by a remote sensing instrument (usually a microwave radiometer). However, the latter is not as generalized, and is rather used for specific field campaigns or local long term observations. Both strategies have led to quite similar coordinate accuracies (using daily GPS observations), at the level of 1–2 mm in the horizontal component and 5–10 mm in the vertical component. The external correction strategy is capable of achieving even higher accuracy under specific conditions. Recent models, including gradients in the parameter estimation strategy have only led to marginal improvement. A major limitation of both strategies seems to be the use of mapping functions for the hydrostatic path delay correction. With the parameter estimation strategy, this limitation applies also to wet path delay correction. The use of numerical weather prediction and analysis models, and/or spaceborne sounding instruments, is suggested for replacing mapping functions and possibly for performing directly the hydrostatic correction. New instruments, such as Raman lidars, might also be used for a more accurate external wet path delay correction in the presence of strong atmospheric inhomogeneity. Further work is still needed for achieving measurements of absolute water vapor distribution in the atmosphere for this purpose. Numéro de notice : A2001-181 Affiliation des auteurs : LOEMI+Ext (1985-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1016/S1464-1895(01)00069-2 Date de publication en ligne : 27/06/2001 En ligne : https://doi.org/10.1016/S1464-1895(01)00069-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102953
in Physics and chemistry of the Earth, Part A: Solid Earth and Geodesy > vol 26 n° 6-8 (2001) . - pp 373 - 383[article]Clustering to improve matched filter detection of weak gas plumes in hyperspectral thermal imagery / C.C. Funk in IEEE Transactions on geoscience and remote sensing, vol 39 n° 7 (July 2001)
[article]
Titre : Clustering to improve matched filter detection of weak gas plumes in hyperspectral thermal imagery Type de document : Article/Communication Auteurs : C.C. Funk, Auteur ; J. Theiler, Auteur ; C.C. Borel, Auteur ; D.A. Roberts, Auteur Année de publication : 2001 Article en page(s) : pp 1410 - 1420 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse de groupement
[Termes IGN] analyse spectrale
[Termes IGN] image hyperspectrale
[Termes IGN] image thermiqueRésumé : (Auteur) The use of matched filters on hyperspectral data has made it possible to detect faint signatures. This study uses a modified k-means clustering to improve matched filter performance. Several simple bivariate cases are examined in detail, and the interaction of filtering and partitioning is discussed. The authors show that clustering can reduce within-class variance and group pixels with similar correlation structures. Both of these features improve filter performance. The traditional k-means algorithm is modified to work with a sample of the image at each iteration and is tested against two hyperspectral datasets. A new “extreme” centroid initialization technique is introduced and shown to speed convergence. Several matched filtering formulations (the simple matched filter, the clutter matched filter, and the saturated matched filter) are compared for a variety of number of classes and synthetic hyperspectral images. The performance of the various clutter matched filter formulations is similar, all are about an order of magnitude better than the simple matched filter. Clustering is found to improve the performance of all matched filter formulations by a factor of two to five. Clustering in conjunction with clutter matched filtering can improve fifty-fold over the simple case, enabling very weak signals to be detected in hyperspectral images. Numéro de notice : A2001-200 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/36.934073 En ligne : https://doi.org/10.1109/36.934073 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21894
in IEEE Transactions on geoscience and remote sensing > vol 39 n° 7 (July 2001) . - pp 1410 - 1420[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-01071 RAB Revue Centre de documentation En réserve L003 Disponible Detection of interannual vegetation responses to climatic variability using AVIRIS data in a coastal savanna in California / M. Garcia in IEEE Transactions on geoscience and remote sensing, vol 39 n° 7 (July 2001)
[article]
Titre : Detection of interannual vegetation responses to climatic variability using AVIRIS data in a coastal savanna in California Type de document : Article/Communication Auteurs : M. Garcia, Auteur ; S.L. Ustin, Auteur Année de publication : 2001 Article en page(s) : pp 1480 - 1490 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse linéaire des mélanges spectraux
[Termes IGN] analyse spectrale
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] image AVIRIS
[Termes IGN] image hyperspectrale
[Termes IGN] littoral
[Termes IGN] pluie
[Termes IGN] savaneRésumé : (Auteur)Ecosystem responses to interannual weather variability are large and superimposed over any long-term directional climatic responses making it difficult to assign causal relationships to vegetation change. Better understanding of ecosystem responses to interannual climatic variability is crucial to predicting long-term functioning and stability. Hyperspectral data have the potential to detect ecosystem responses that are undetected by broadband sensors and can be used to scale to coarser resolution global mapping sensors, e.g., advanced very high resolution radiometer (AVHRR) and MODIS. This research focused on detecting vegetation responses to interannual climate using the airborne visible-infrared imaging spectrometer (AVIRIS) data over a natural savanna in the Central Coast Range in California. Results of linear spectral mixture analysis and assessment of the model errors were compared for two AVIRIS images acquired in spring of a dry and a wet year. The results show that mean unmixed fractions for these vegetation types were not significantly different between years due to the high spatial variability within the landscape. However, significant community differences were found between years on a pixel basis, underlying the importance of site-specific analysis. Multitemporal hyperspectral coverage is necessary to understand vegetation dynamics. Numéro de notice : A2001-206 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/36.934079 En ligne : https://doi.org/10.1109/36.934079 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21900
in IEEE Transactions on geoscience and remote sensing > vol 39 n° 7 (July 2001) . - pp 1480 - 1490[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-01071 RAB Revue Centre de documentation En réserve L003 Disponible Discrimination of arid vegetation with airborne multispectral scanner hyperspectral imagery / M. Lewis in IEEE Transactions on geoscience and remote sensing, vol 39 n° 7 (July 2001)
[article]
Titre : Discrimination of arid vegetation with airborne multispectral scanner hyperspectral imagery Type de document : Article/Communication Auteurs : M. Lewis, Auteur ; V. Joosten, Auteur ; A.A. DE Gasparis, Auteur Année de publication : 2001 Article en page(s) : pp 1471 - 1479 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] airborne multispectral scanner
[Termes IGN] analyse spectrale
[Termes IGN] image aérienne
[Termes IGN] image hyperspectrale
[Termes IGN] végétation
[Termes IGN] zone arideNuméro de notice : A2001-205 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/36.934078 En ligne : https://doi.org/10.1109/36.934078 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21899
in IEEE Transactions on geoscience and remote sensing > vol 39 n° 7 (July 2001) . - pp 1471 - 1479[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-01071 RAB Revue Centre de documentation En réserve L003 Disponible Spectral mixture analysis of simulated thermal infrared spectrometry data: an initial temperature estimate bounded TESSMA search approach / E.F. Collins in IEEE Transactions on geoscience and remote sensing, vol 39 n° 7 (July 2001)PermalinkA spectral mixture process conditioned by Gibbs-based partitioning / R.S. Rand in IEEE Transactions on geoscience and remote sensing, vol 39 n° 7 (July 2001)PermalinkApport de l'altimétrie par laser aéroporté à la cartographie des estrans : expérimentation de l'anse de l'aiguillon / G. Barreau in XYZ, n° 87 (juin - août 2001)PermalinkEffect of small-scale atmospheric inhomogeneity on positioning accuracy with GPS / Olivier Bock in Geophysical research letters, vol 28 n° 11 (1 June 2001)PermalinkModifications of Tanaka's illuminated contour method / Patrick Kennelly in Cartography and Geographic Information Science, vol 28 n° 2 (April 2001)PermalinkAn interactive approach to analytical relief shading / J. Jenny in Cartographica, vol 38 n° 1 - 2 (March 2001)PermalinkStudy of external path delay correction techniques for high accuracy height determination with GPS / Olivier Bock in Physics and chemistry of the Earth, Part A: Solid Earth and Geodesy, vol 26 n° 3 ([01/03/2001])PermalinkAnalysis of refraction influences in geodesy using image processing and turbulence models / Philipp Flach (2001)PermalinkLe canal MIR de Spot4 / Guy Flament (2001)PermalinkDevelopment of a dispersometer for the implementation into geodetic high-accuracy direction measurement systems / Burkhard Böckem (2001)PermalinkDevelopment of a solar spectro-irradiometer for the validation of remotely sensed hyperspectral images / A. Barducci (2001)PermalinkEtude des relations spécifiques entre végétation et roches du massif de Ronda par télédétection hyperspectrale AVIRIS (1991) et HYMAP (2000) / Guillaume Hallereau (2001)PermalinkFundamentals of physics and chemistry of the atmosphere / G. Visconti (2001)PermalinkInfluence of the three-dimensional effects on the simulation of landscapes in thermal infrared / T. Poglio (2001)PermalinkMicrostrip filters for RF/microwave applications / J.S. Hong (2001)PermalinkMonitoring and water pollution modelling of the Bosphorus by regression analysis using multitemporal Landsat-TM data / H. Gonca Coskun (2001)PermalinkA numerical analysis of the accuracy of laboratory and field goniometer measurements / N. Widen (2001)PermalinkPermalinkPermalinkPermalink