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Reducing the dimensionality of plant spectral databases / I.E. Bell in IEEE Transactions on geoscience and remote sensing, vol 42 n° 3 (March 2004)
[article]
Titre : Reducing the dimensionality of plant spectral databases Type de document : Article/Communication Auteurs : I.E. Bell, Auteur ; V.G. Baranoski, Auteur Année de publication : 2004 Article en page(s) : pp 570 - 576 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] analyse en composantes principales
[Termes IGN] base de données
[Termes IGN] biologie
[Termes IGN] réflectance végétale
[Termes IGN] transmittance
[Termes IGN] végétationRésumé : (Auteur) Ground-based measurements of plant reflectance and transmittance are essential for remote sensing projects oriented toward agriculture, forestry, and ecology. This paper examines the application of principal components analysis (PCA) in the storage and reconstruction of such plant spectral data. A novel piecewise PCA approach (PPCA), which takes into account the biological factors that affect the interaction of solar radiation with plants, is also proposed. These techniques are compared through experiments involving the reconstruction of reflectance and transmittance curves for herbaceous and woody specimens. The spectral data used in these experiments were obtained from the Leaf Optical Properties Experiment (LOPEX) database. The reconstructions were performed aiming at a root-mean-square error (RMSE) lower than 1%. The results of these experiments indicate that PCA can effectively reduce the dimensionality of plant spectral databases from the visible to the infrared regions of the light spectrum, and that the PPCA approach can further maximize the accuracy/cost ratio of the storage and reconstruction of plant spectral reflectance and transmittance data. Numéro de notice : A2004-155 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2003.821697 En ligne : https://doi.org/10.1109/TGRS.2003.821697 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26682
in IEEE Transactions on geoscience and remote sensing > vol 42 n° 3 (March 2004) . - pp 570 - 576[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-04031 RAB Revue Centre de documentation En réserve L003 Disponible Using maximum likelihood (ML) and maximum a prior probability (MAP) in iterative self-organizing data (Isodata) / Hassan A. Karimi in Geocarto international, vol 19 n° 1 (March - May 2004)
[article]
Titre : Using maximum likelihood (ML) and maximum a prior probability (MAP) in iterative self-organizing data (Isodata) Type de document : Article/Communication Auteurs : Hassan A. Karimi, Auteur ; Jinzheng Peng, Auteur Année de publication : 2004 Article en page(s) : pp 29 - 36 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] carte de Kohonen
[Termes IGN] classification non dirigée
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] image à très haute résolution
[Termes IGN] image satellite
[Termes IGN] itérationRésumé : (Auteur) With the availability of high-resolution satellite imagery featuring as high as 1 meter resolution in the panchromatic mode and 3-meter resolution in the multispectral mode, there is an interest by many new commercial and public service applications such as cellular telephones coverage area design, urban/land cover planning, and real estate marketing to extract features from images automatically. To that end, the demand for unsupervised classification techniques is growing. In this paper, the Maximum Likelihood (ML) and Maximum A prior Probability (MAP) algorithms are used as decision rules to find boundaries of classes computed by the Iterative Self-Organizing Data (ISOADATA) algorithm. Different satellite images with different resolutions were used to experiment with these algorithms. The results of comparing and analyzing the algorithms revealed that MAP-ISODATA performed better than ML-ISODATA even when the same initial matrix was used. It was shown that there was no significant différence between ML-ISODATA and MAP-ISODATA in terms of accuracy. It was also realized that better results could be obtained if homogenous initialization strategies were used. Numéro de notice : A2004-232 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106040408542296 Date de publication en ligne : 02/01/2008 En ligne : https://doi.org/10.1080/10106040408542296 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26759
in Geocarto international > vol 19 n° 1 (March - May 2004) . - pp 29 - 36[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-04011 RAB Revue Centre de documentation En réserve L003 Disponible Estimation of land surface temperature-vegetation abundance relationship for urban heat island studies / Q. Wenger in Remote sensing of environment, vol 89 n° 4 (29/02/2004)
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Titre : Estimation of land surface temperature-vegetation abundance relationship for urban heat island studies Type de document : Article/Communication Auteurs : Q. Wenger, Auteur ; Dong Lu, Auteur ; J. Schubring, Auteur Année de publication : 2004 Article en page(s) : pp 467 - 483 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse des mélanges spectraux
[Termes IGN] classification
[Termes IGN] exitance spectrale
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] température de surface
[Termes IGN] texture d'image
[Termes IGN] Thematic Mapper
[Termes IGN] traitement d'image
[Termes IGN] zone urbaineRésumé : (Auteur) Remote sensing of urban heat islands (UHls) has traditionally used the Normalized Difference Vegetation Index (NDVI) as the indicator of vegetation abundance to estimate the land surface temperature (LST)-vegetation relationship. This study investigates the applicability of vegetation fraction derived from a spectral mixture model as an alternative indicator of vegetation abundance. This is based on examination of a Landsat Enhanced Thematic Mapper Plus (ETM+) image of Indianapolis City, IN, USA, acquired on June 22, 2002. The transformed ETM+ image was unmixed into three fraction images (green vegetation, dry soil, and shade) with a constrained least-square solution. These fraction images were then used for land cover classification based on a hybrid classification procedure that combined maximum likelihood and decision tree algorithms. Results demonstrate that LST possessed a slightly stronger negative correlation with the unmixed vegetation fraction than with NDVI for all land cover types across the spatial resolution (30 to 960 m). Correlations reached their strongest at the 120-m resolution, which is believed to be the operational scale of LST, NDVI, and vegetation fraction images. Fractal analysis of image texture shows that the complexity of these images increased initially with pixel aggregation and peaked around 120 m, but decreased with farther aggregation. The spatial variability of texture in LST was positively correlated with those in NDVI and in vegetation fraction. The interplay between thermal and vegetation dynamics in the context of different land cover types leads to the variations in spectral radiance and texture in LST. These variations are also present in the other imagery, and are responsible for the spatial patterns of urban heat islands. It is suggested that the areal measure of vegetation abundance by unmixed vegetation fraction has a more direct correspondence with the radiative, thermal, and moisture properties of the Earth's surface that determine LST. Numéro de notice : A2004-072 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.11.005 En ligne : https://doi.org/10.1016/j.rse.2003.11.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26600
in Remote sensing of environment > vol 89 n° 4 (29/02/2004) . - pp 467 - 483[article]Carbon mass fluxes of forests in Belgium determined with low resolution optical sensors / F. Veroustraete in International Journal of Remote Sensing IJRS, vol 25 n° 4 (February 2004)
[article]
Titre : Carbon mass fluxes of forests in Belgium determined with low resolution optical sensors Type de document : Article/Communication Auteurs : F. Veroustraete, Auteur ; H. Sabbe, Auteur ; D.P. Rasse, Auteur ; L. Bertels, Auteur Année de publication : 2004 Article en page(s) : pp 769 - 792 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] Belgique
[Termes IGN] bilan du carbone
[Termes IGN] classificateur paramétrique
[Termes IGN] corrélation
[Termes IGN] covariance
[Termes IGN] écosystème forestier
[Termes IGN] forêt
[Termes IGN] image NOAA-AVHRR
[Termes IGN] image optique
[Termes IGN] image SPOT-Végétation
[Termes IGN] turbulenceRésumé : (Auteur) The primary objective of this paper is to describe the validation of a parametric model (C-Fix) designed to estimate the basic carbon mass fluxes of forests in Belgium. Most validation efforts in the literature are based on point measurements. Since landscapes in Belgium are quite heterogeneous, the spatial up-scaling of a point measurement to the level of a sensor pixel is a crucial issue. Process based models quite often have a large set of input variables, some of them hardly available or not measurable on a regional basis; on the other hand most of the process based models possess a prognostic capacity. The parametric C-Fix model estimates carbon mass fluxes from local, regional to continental scales. It ingests only a modest number of meteorological input variables, including satellite observations. Parametric models do not possess a prognostic capacity, but the spatial up-scaling by the use of remote sensing data is much more straightforward than with process models. In this paper, we describe the validation of C-Fix with eddy covariance NEP (net ecosystem production) measurements and further applied C-Fix for the mapping of the geographical distribution of carbon mass fluxes over the entire Belgian territory, using NOAA-AVHRR (1997) and SPOT4-VGT imagery (April 1998-March 1999). We combine a forest probability map, derived from NOAA data for 1997 with the mapped estimates of Belgian NEP to obtain forest NEP per image pixel. Forest NEP is validated regionally, with measurements of carbon exchange obtained at two Belgian Euroflux eddy covariance tower sites (the Brasschaat, 'Inslag' and Vielsalm, 'Tinscubois' forest sites). A correlation analysis is performed for the estimated forest NEPs at both Euroflux sites and the NEP measured there, assumed to be primarily from forest. Finally, a correlation analysis with a process-based stand scale model (ASPECTS) is performed for the two forest sites, as a cross cheek on the validation results. Our results demonstrate that a parametric model, like C-Fix, provides a good basis to estimate the evolution and geographical distribution of the main constituents of the carbon budget of terrestrial ecosystems, in this study specifically forest ecosystems at the regional scale (Belgium). Numéro de notice : A2004-075 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000115238 En ligne : https://doi.org/10.1080/0143116031000115238 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26603
in International Journal of Remote Sensing IJRS > vol 25 n° 4 (February 2004) . - pp 769 - 792[article]Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 080-04041 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Improving tropical forest mapping using multi-date Landsat TM data and pre-classification image smoothing / C. Tottrup in International Journal of Remote Sensing IJRS, vol 25 n° 4 (February 2004)
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Titre : Improving tropical forest mapping using multi-date Landsat TM data and pre-classification image smoothing Type de document : Article/Communication Auteurs : C. Tottrup, Auteur Année de publication : 2004 Article en page(s) : pp 717 - 730 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse diachronique
[Termes IGN] canopée
[Termes IGN] carte de la végétation
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] écosystème
[Termes IGN] forêt tropicale
[Termes IGN] image Landsat-TM
[Termes IGN] image multitemporelle
[Termes IGN] lissage de donnéesRésumé : (Auteur) The present study explores the possibility of using Landsat imagery for mapping tropical forest types with relevance to forest ecosystem services. The central part in the classification process is the use of multi-date image data and pre-classification image smoothing. The study argues that multi-date imagery contains information on phenological and canopy structural properties and shows how the use of multi-date imagery has a significant impact on classification accuracy. Furthermore, the study shows the value of applying small kernel smoothing filters to reduce in-class spectral variability and enhance between-class spectral separability. Making use of these approaches and a maximum likehood algorithm, six tropical forest types were classified with an overall accuracy of 90.94%, and with individual forest classes mapped with accuracies above 75.19% (user's accuracy) and above 74.17% (producer accuracy). Numéro de notice : A2004-074 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160310001598926 En ligne : https://doi.org/10.1080/01431160310001598926 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26602
in International Journal of Remote Sensing IJRS > vol 25 n° 4 (February 2004) . - pp 717 - 730[article]Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 080-04041 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Delineation of forest/nonforest land use classes using nearest neighbor methods / R. Haapanen in Remote sensing of environment, vol 89 n° 3 (15/02/2004)PermalinkLineament detection on Mount Cameroon during the 1999 volcanic eruptions using Landsat ETM / E.E. Nama in International Journal of Remote Sensing IJRS, vol 25 n° 3 (February 2004)PermalinkApproaches to fractional land cover and continuous field mapping: a comparative assessment over the BOREAS [BOReal Ecosystem Atmosphere Study] study region / R. Fernandes in Remote sensing of environment, vol 89 n° 2 (30/01/2004)PermalinkRemote sensing in BOREAS [BOReal Ecosystem Atmosphere Study]: Lessons learned / John A. Gamon in Remote sensing of environment, vol 89 n° 2 (30/01/2004)PermalinkMapping rice field anopheline breeding habitats in Mali, West Africa, using Landsat ETM+ sensor data / M.A. Diuk-Wasser in International Journal of Remote Sensing IJRS, vol 25 n° 2 (January 2004)PermalinkUnsupervised 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)PermalinkHyperspectral 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)PermalinkSpectral characteristics and feature selection of hyperspectral remote sensing data / X. Jiang in International Journal of Remote Sensing IJRS, vol 25 n° 1 (January 2004)PermalinkThe EuroSTARRS airborne campaign in support of the SMOS mission: first results over land surfaces / K. Saleh in International Journal of Remote Sensing IJRS, vol 25 n° 1 (January 2004)PermalinkAutomated subpixel photobathymetry and water quality mapping / R.L. Huguenin in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 1 (January 2004)Permalink