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Unsupervised classification of hyperspectral data: an ICA mixture model based approach / Chintan A. Shah in International Journal of Remote Sensing IJRS, vol 25 n° 2 (January 2004)
[article]
Titre : Unsupervised classification of hyperspectral data: an ICA mixture model based approach Type de document : Article/Communication Auteurs : Chintan A. Shah, Auteur ; M.K. Arora, Auteur ; P.K. Varshney, Auteur Année de publication : 2004 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse en composantes indépendantes
[Termes IGN] classification non dirigée
[Termes IGN] image AVIRIS
[Termes IGN] image hyperspectrale
[Termes IGN] précision de la classificationRésumé : (Auteur) Conventional unsupervised classification algorithms that model the data in each class with a multivariate Gaussian distribution are often inappropriate, as this assumption is frequently not satisfied by the remote sensing data. In this Letter, a new algorithm based on independent component analysis (ICA) is presented. The ICA mixture model (ICAMM) algorithm that models class distributions as non-Gaussian densities has been employed for unsupervised classification of a test image from the AVIRIS sensor. A number of feature-extraction techniques have also been examined that serve as a preprocessing step to reduce the dimensionality of the hyperspectral data. The proposed ICAMM algorithm results in significant increase in the classification accuracy over that obtained from the conventional K-means algorithm for land cover classification. Numéro de notice : A2004-060 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160310001618040 En ligne : https://doi.org/10.1080/01431160310001618040 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26588
in International Journal of Remote Sensing IJRS > vol 25 n° 2 (January 2004)[article]Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 080-04021 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Hyperspectral monitoring of physiological parameters of wheat during a vegetation period using AVIS data / N. Oppelt in International Journal of Remote Sensing IJRS, vol 25 n° 1 (January 2004)
[article]
Titre : Hyperspectral monitoring of physiological parameters of wheat during a vegetation period using AVIS data Type de document : Article/Communication Auteurs : N. Oppelt, Auteur ; W. Mauser, Auteur Année de publication : 2004 Article en page(s) : pp 145 - 159 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse de données
[Termes IGN] analyse diachronique
[Termes IGN] Bavière (Allemagne)
[Termes IGN] blé (céréale)
[Termes IGN] classificateur paramétrique
[Termes IGN] hétérogénéité sémantique
[Termes IGN] image AVIRIS
[Termes IGN] image hyperspectrale
[Termes IGN] indice de végétation
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] réflectance végétale
[Termes IGN] saison
[Termes IGN] surveillance agricole
[Termes IGN] zone humideRésumé : (Auteur) Information on the quantity and spatial distribution of canopy physiological and biochemical components is of importance for the study of nutrient cycles, productivity, vegetation stress and, more recently, in driving ecosystem models. In this context, remote sensing can play a unique and essential role because of its ability to acquire synoptic information at different time and space scales. This paper presents parts of a two-year field and laboratory study with the new airborne hyperspectral sensor, the Airborne Visible near Infrared Imaging Spectrometer (AVIS), over a test site in the Bavarian Alpine foothills, Germany (48' 8'N, 11°17' E ). The 80-band AVIS was developed at the Department for Earth and Environmental Sciences of the LudwigMaximiliansUniversity Munich and records the 550-1000 mn spectral range. Using this system, 18 hyperspectral datasets were collected between April and September of 1999 and 2000. Weekly measurements of several plant parameters (height, biomass, leaf chlorophyll content, leaf nitrogen content) were carried out during these time periods on three (1999) and six (2000) fields of winter wheat, whereby two different cultivars were investigated in 2000. After system correction and calibration, the hyperspectral data were atmospherically corrected and calibrated to reflectance. The resulting spectra were analysed for their chemical compounds. The statistical analysis was carried out using the Chlorophyll Absorption Integral (CAI) in comparison to established indices: Optimized Soil-Adjusted Vegetation Index (OSAVI) and hyperspectral Normalized Difference Vegetation Index (hNDVI). Both the chlorophyll and nitrogen content of the leaves showed good correlations with CAI on a field mean basis. These results as well as two-dimensional information on these parameters are presented to provide information about the spatial heterogeneity within a field. Numéro de notice : A2004-036 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000115300 En ligne : https://doi.org/10.1080/0143116031000115300 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26564
in International Journal of Remote Sensing IJRS > vol 25 n° 1 (January 2004) . - pp 145 - 159[article]Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 080-04011 RAB Revue Centre de documentation En réserve L003 Exclu du prêt AVIRIS measurements of chlorophyll, suspended minerals, dissolved organic carbon, and turbidity in the Neuse River, North Carolina / M.A. Karaska in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 1 (January 2004)
[article]
Titre : AVIRIS measurements of chlorophyll, suspended minerals, dissolved organic carbon, and turbidity in the Neuse River, North Carolina Type de document : Article/Communication Auteurs : M.A. Karaska, Auteur ; R.L. Huguenin, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 125 - 133 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse en composantes principales
[Termes IGN] Caroline du Nord (Etats-Unis)
[Termes IGN] écosystème
[Termes IGN] eutrophisation
[Termes IGN] image AVIRIS
[Termes IGN] mesure de la qualité
[Termes IGN] milieu aquatique (eau douce)
[Termes IGN] qualité des eaux
[Termes IGN] rivière
[Termes IGN] turbidité des eauxRésumé : (Auteur) Many aquatic ecosystems in the United States and worldwide are impaired by the over-enrichment of waters by nutrients. In advanced stages, the process of eutrophication can cause harmful algae blooms. This research retrieved the concentrations of suspended chlorophyll (Chl), suspended minerals (SM), colored dissolved organic carbon (DOC), and turbidity (total attenuation) from AVIRIS imagery of a severely overenriched waterway in North Carolina, and evaluated if these parameters could be used as indicators of conditions leading to algae blooms. A digital image processing algorithm called Qsc1 (Quantitative Shoreline Characterization, Version 1.0) was used. The retrieved water quality parameter values were tested by statistical comparisons to field measurements made at the time of the AVIRIS data collection. Applying Qsc1 to AVIRIS imagery resulted in measurements of Chl that correlated well with field measurements (r = 0.84). Problems with field sampling prevented the assessment of retrieveSM and Doc. The statistical correlation analysis indicated that, for comparison to remotely sensed data, field measurements in the steadily flowing Neuse River must be collected within two hours of the imagery. Thematic maps of each water quality parameter were generated from the imagery and evaluated. The maps of Chl showed spatial patterns consistent with the field data and circulation of the river, and indicated potential point and non-point sources. Statistical and principle component analyses were used to assess whether the AVIRIS water quality measurements were directly or indirectly related to parameters and conditions indicative of nutrient loading and algae blooms that were measured in the field. The AVIRIS measurements were used to create a new index of eutrophication, the Algae Production Potential Index (Appi), for the purpose of mapping where conditions of high nutrient loading and potential algae blooms exist. The index uses direct measurements of Chl, Doc, and Sm (as a surrogate for phosphate). These measurements are combined in a Gis model based on ecological relationships. Although not field verified, the APPI map shows patterns of algae bloom conditions that are similar in size, scale, and location to previous blooms in the Neuse. Numéro de notice : A2004-006 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.70.1.125 En ligne : http://dx.doi.org/10.14358/PERS.70.1.125 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26534
in Photogrammetric Engineering & Remote Sensing, PERS > vol 70 n° 1 (January 2004) . - pp 125 - 133[article]Spectral reflectance characterization of shallow lakes from the Brazilian pantanal wetlands with field and airborne hyperspectral data / L.S. Galvao in International Journal of Remote Sensing IJRS, vol 24 n° 21 (November 2003)
[article]
Titre : Spectral reflectance characterization of shallow lakes from the Brazilian pantanal wetlands with field and airborne hyperspectral data Type de document : Article/Communication Auteurs : L.S. Galvao, Auteur ; W. Pereira Filho, Auteur ; M.M. Abdon, Auteur ; et al., Auteur Année de publication : 2003 Article en page(s) : pp 4093 - 4112 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse en composantes principales
[Termes IGN] Brésil
[Termes IGN] hydrographie de surface
[Termes IGN] image aérienne
[Termes IGN] image AVIRIS
[Termes IGN] image hyperspectrale
[Termes IGN] lac
[Termes IGN] réflectance spectrale
[Termes IGN] sédiment
[Termes IGN] zone humideRésumé : (Auteur) The relationships between field water reflectance spectra and physicochemical data of seven freshwater and five saltwater lakes from the Brazilian Pantanal wetlands were characterized. Selection of the lakes was based on previous inspection of the Airborne Visible/infrared Imaging Spectrometer (AVIRIS) images. Principal component analysis (PCA) was used to identify homogeneous groups of lakes, in which the regression relationships were evaluated. The continuum removal method was applied to characterize minor spectral variations in the depth of the absorption bands present in field and image spectra. The results showed lakes with very distinct spectral characteristics. The transition from the freshwater to the saltwater lakes was characterized by lower values of depth and Secchi depth, larger concentrations of dissolved organic carbon (DOC), total suspended sediments (TSS), calcium (Ca), magnesium (Mg), sodium (Na) and potassium (K), and higher values of pH and electrical conductivity. The saline lakes presented a higher overall reflectance in the 400900 nm range than the freshwater lakes, as indicated by the first principal component. From the optically active constituents analysed, DOC better explained variations in water reflectance. The discrimination of the saltwater lakes along the second principal component was due to the decrease in the chlorophyll (Chl) and to the increase in the DOC concentrations from the greenish to the bluish saline lakes. The AVIRIS instrument was able to detect the narrow 630 nm absorption band present in field water reflectance spectra. Numéro de notice : A2003-303 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000070382 En ligne : https://doi.org/10.1080/0143116031000070382 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22599
in International Journal of Remote Sensing IJRS > vol 24 n° 21 (November 2003) . - pp 4093 - 4112[article]Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 080-03211 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Spectral resolution requirements for mapping urban areas / Martin Herold in IEEE Transactions on geoscience and remote sensing, vol 41 n° 9 (September 2003)
[article]
Titre : Spectral resolution requirements for mapping urban areas Type de document : Article/Communication Auteurs : Martin Herold, Auteur ; M.E. Gardner, Auteur ; D.A. Roberts, Auteur Année de publication : 2003 Article en page(s) : pp 1907 - 1919 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] cartographie urbaine
[Termes IGN] classification
[Termes IGN] image AVIRIS
[Termes IGN] image hyperspectrale
[Termes IGN] image Ikonos
[Termes IGN] image Landsat-TM
[Termes IGN] image multibande
[Termes IGN] image optique
[Termes IGN] milieu urbain
[Termes IGN] occupation du sol
[Termes IGN] précision de la classificationRésumé : (Auteur) This study evaluated how spectral resolution of spatial resolution optical remote sensing data influences detailed mapping of urban land cover. A comprehensive regional spectral library and low altitude data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) were used to characterize the spectral properties of urban land cover. The Bhattacharyya distance was applied as a measure of spectral separability to determine a most suitable subset of 14 AVIRIS bands for urban mapping. We evaluated the performance of this spectral setting versus common multispectral sensors such as Ikonos by assessing classification accuracy for 26 urban land cover classes. Significant limitations for current multispectral sensors were identified, where the location and broadband character of the spectral bands only marginally resolved the complex spectral characteristics of the urban environment, especially for built surface types. However, the AVIRIS classification accuracy did not exceed 66.6% for 22 urban cover types, primarily due to spectral similarities of specific urban materials and high withinclass variability. Numéro de notice : A2003-248 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2003.815238 En ligne : https://doi.org/10.1109/TGRS.2003.815238 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22543
in IEEE Transactions on geoscience and remote sensing > vol 41 n° 9 (September 2003) . - pp 1907 - 1919[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-03091 RAB Revue Centre de documentation En réserve L003 Disponible Analysis of hyperspectral data for estimation of temperate forest canopy nitrogen concentration: Comparison between an Airborne (AVIRIS) and a spaceborne (Hyperion) sensor / M.L. Smith in IEEE Transactions on geoscience and remote sensing, vol 41 n° 6 (June 2003)PermalinkFusion of hyperspectral and radar data using the IHS transformation to enhance urban surface features / C.M. Chen in ISPRS Journal of photogrammetry and remote sensing, vol 58 n° 1-2 (June - December 2003)PermalinkHyperspectral texture recognition using a multiscale opponent representation / M. Shi in IEEE Transactions on geoscience and remote sensing, vol 41 n° 5 (May 2003)PermalinkRadiative transfer codes applied to hyperspectral data for the retrieval of surface reflectance / K. Staenz in ISPRS Journal of photogrammetry and remote sensing, vol 57 n° 3 (December 2002 - January 2003)PermalinkBest-bases feature extraction algorithms for classification of hyperspectral data / Satish Kumar in IEEE Transactions on geoscience and remote sensing, vol 39 n° 7 (July 2001)PermalinkDetection 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)PermalinkA new search algorithm for feature selection in hyperspectral remote sensing images / S.B. Serpico in IEEE Transactions on geoscience and remote sensing, vol 39 n° 7 (July 2001)PermalinkEtude des relations spécifiques entre végétation et roches du massif de Ronda par télédétection hyperspectrale AVIRIS (1991) et HYMAP (2000) / Guillaume Hallereau (2001)PermalinkEtudes des mélanges spectraux visible et infrarouge pour la cartographie pétrologique sur images Aviris / N. Goulli (1998)PermalinkApport de la modélisation du transfert radiatif pour l'étude des écosystèmes forestiers par télédétection / V. Pinel (1997)Permalink