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Cartographic redundancy in reducing change blindness in detecting extreme values in spatio-temporal maps / Paweł Cybulski in ISPRS International journal of geo-information, vol 7 n° 1 (January 2018)
[article]
Titre : Cartographic redundancy in reducing change blindness in detecting extreme values in spatio-temporal maps Type de document : Article/Communication Auteurs : Paweł Cybulski, Auteur ; Beata Medyńska-Gulij, Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] cécité au changement
[Termes IGN] données spatiotemporelles
[Termes IGN] redondance de données
[Termes IGN] test de performance
[Termes IGN] vision
[Vedettes matières IGN] GéovisualisationRésumé : (Auteur) The article investigates the possibility of using cartographic redundancy to reduce the change blindness effect on spatio-temporal maps. Unlike in the case of previous research, the authors take a look at various methods of cartographic presentation and modify the visual variables in order to see how those modifications affect the user’s perception of changes on spatio-temporal maps. The study described in the following article was the first attempt at minimizing the change blindness phenomenon by manipulating graphical parameters of cartographic visualization and using various quantitative mapping methods. Research shows that cartographic redundancy is not enough to completely resolve the problem of change blindness; however, it might help reduce it. Numéro de notice : A2018-041 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi7010008 En ligne : https://doi.org/10.3390/ijgi7010008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89263
in ISPRS International journal of geo-information > vol 7 n° 1 (January 2018)[article]
Titre : Foveon VS Bayer: Comparison of 3D reconstruction performances Type de document : Mémoire Auteurs : Pierre Bodin, Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2018 Importance : 43 p. Format : 21 x 30 cm Note générale : Bibliographie
Rapport de projet, stage pluridisciplinaire, cycle ING2Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] analyse comparative
[Termes IGN] caméra numérique
[Termes IGN] filtre de Bayer
[Termes IGN] géométrie de l'image
[Termes IGN] longueur d'onde
[Termes IGN] pas d'échantillonnage au sol
[Termes IGN] qualité radiométrique (image)
[Termes IGN] reconstruction 3D
[Termes IGN] semis de points
[Termes IGN] test de performanceIndex. décimale : PROJET Mémoires : Rapports de projet - stage des ingénieurs de 2e année Résumé : (auteur) La plupart des appareils photos modernes capturent les longueurs d’onde du monde à travers un filtre coloré appelé communément filtre de Bayer. Un tel dispositif attribue à chaque photo-site une valeur radiométrique correspondant à un seul canal (rouge, vert ou bleu). Les valeurs manquantes sont reconstituées par interpolation lors d’un traitement appelé dé-matriçage. Certains appareils, notamment ceux développés par Sigma, utilisent les propriétés du silicone pour capturer, dans chaque photo-site, des informations issues de toutes les longueurs d’onde du monde. Il s’agit de la technologie Foveon. L’objectif de mon travail est de comparer les performances de ces deux types de technologies pour la reconstruction de modèle 3D. Les appareils photos utilisés sont le Nikon D90 (technologie Bayer) et le Sigma Sd1 Merill (technologie Foveon). Le travail effectué se décompose en deux phases, une première phase d’évaluation de la qualité de l’information reconstruite par les algorithmes de dé-matriçage, dans un contexte image. La deuxième compare les performances des appareils photos pour la reconstruction de modèle 3d pour un site test de type mur-peint. Note de contenu : Introduction
1- Bayer and Foveon
2- Demosaicing testing
3- Point Clouds comparison
ConclusionNuméro de notice : 21805 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Mémoire de projet pluridisciplinaire Organisme de stage : Cyprus University of Technology (Chypre) Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91294 Réservation
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Foveon VS Bayer... - pdf auteurAdobe Acrobat PDF The use of low-cost, single-frequency GNSS receivers in mapping surveys / M. Tsakiri in Survey review, vol 50 n° 358 (January 2018)
[article]
Titre : The use of low-cost, single-frequency GNSS receivers in mapping surveys Type de document : Article/Communication Auteurs : M. Tsakiri, Auteur ; A. Sioulis, Auteur ; George Piniotis, Auteur Année de publication : 2018 Article en page(s) : pp 46 - 56 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] coût
[Termes IGN] Grèce
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] récepteur GNSS
[Termes IGN] récepteur monofréquence
[Termes IGN] test de performanceRésumé : (auteur) The emergence of low-cost, navigation-type receivers capable to provide carrier-phase data (the so-called high-sensitivity carrier-phase positioning) has been steadily growing over the recent years. The aim of this study was to evaluate the positioning performance of a high-sensitivity receiver in a network real-time kinematic environment for mapping surveying applications. Specifically, using as rover receiver the u-blox NEO-7P module and the low-cost antenna Tallysman TW2410, sets of data were collected for the purpose of mapping surveying. The external accuracy of the obtained solutions is considered using different positioning techniques and the internal indicators of the system during real-time kinematic (RTK) positioning are assessed. The assessment indicates that in benign environments this type of receivers produce results that are comparable to RTK positioning using geodetic receivers and with a significantly lower cost. Numéro de notice : A2018-177 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/00396265.2016.1222344 Date de publication en ligne : 16/09/2016 En ligne : https://doi.org/10.1080/00396265.2016.1222344 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89821
in Survey review > vol 50 n° 358 (January 2018) . - pp 46 - 56[article]Per-pixel bias-variance decomposition of continuous errors in data-driven geospatial modeling : A case study in environmental remote sensing / Jing Gao in ISPRS Journal of photogrammetry and remote sensing, vol 134 (December 2017)
[article]
Titre : Per-pixel bias-variance decomposition of continuous errors in data-driven geospatial modeling : A case study in environmental remote sensing Type de document : Article/Communication Auteurs : Jing Gao, Auteur ; James E. Burt, Auteur Année de publication : 2017 Article en page(s) : pp 110 - 121 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] apprentissage automatique
[Termes IGN] classification pixellaire
[Termes IGN] décomposition
[Termes IGN] données environnementales
[Termes IGN] erreur absolue
[Termes IGN] erreur systématique
[Termes IGN] image Landsat
[Termes IGN] précision de l'estimation
[Termes IGN] surface imperméable
[Termes IGN] test de performance
[Termes IGN] varianceRésumé : (Auteur) This study investigates the usefulness of a per-pixel bias-variance error decomposition (BVD) for understanding and improving spatially-explicit data-driven models of continuous variables in environmental remote sensing (ERS). BVD is a model evaluation method originated from machine learning and have not been examined for ERS applications. Demonstrated with a showcase regression tree model mapping land imperviousness (0–100%) using Landsat images, our results showed that BVD can reveal sources of estimation errors, map how these sources vary across space, reveal the effects of various model characteristics on estimation accuracy, and enable in-depth comparison of different error metrics. Specifically, BVD bias maps can help analysts identify and delineate model spatial non-stationarity; BVD variance maps can indicate potential effects of ensemble methods (e.g. bagging), and inform efficient training sample allocation – training samples should capture the full complexity of the modeled process, and more samples should be allocated to regions with more complex underlying processes rather than regions covering larger areas. Through examining the relationships between model characteristics and their effects on estimation accuracy revealed by BVD for both absolute and squared errors (i.e. error is the absolute or the squared value of the difference between observation and estimate), we found that the two error metrics embody different diagnostic emphases, can lead to different conclusions about the same model, and may suggest different solutions for performance improvement. We emphasize BVD’s strength in revealing the connection between model characteristics and estimation accuracy, as understanding this relationship empowers analysts to effectively steer performance through model adjustments. Numéro de notice : A2017-731 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2017.11.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2017.11.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=88429
in ISPRS Journal of photogrammetry and remote sensing > vol 134 (December 2017) . - pp 110 - 121[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2017121 RAB Revue Centre de documentation En réserve L003 Disponible 081-2017122 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt 081-2017123 DEP-EXM Revue Saint-Mandé Dépôt en unité Exclu du prêt Improved atmospheric correction and chlorophyll-a remote sensing models for turbid waters in a dusty environment / Maryam R. Al Shehhi in ISPRS Journal of photogrammetry and remote sensing, vol 133 (November 2017)
[article]
Titre : Improved atmospheric correction and chlorophyll-a remote sensing models for turbid waters in a dusty environment Type de document : Article/Communication Auteurs : Maryam R. Al Shehhi, Auteur ; Imen Gherboidj, Auteur ; Hosni Gherida, Auteur Année de publication : 2017 Article en page(s) : pp 46 - 60 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse comparative
[Termes IGN] Arabie
[Termes IGN] chlorophylle
[Termes IGN] correction atmosphérique
[Termes IGN] couleur de l'océan
[Termes IGN] eau de mer
[Termes IGN] image Aqua-MODIS
[Termes IGN] image Terra-MODIS
[Termes IGN] test de performance
[Termes IGN] turbidité océaniqueRésumé : (Auteur) This study presents a comprehensive assessment of the performance of the commonly used atmospheric correction models (NIR, SWIR, NIR-SWIR and FM) and ocean color products (OC3 and OC2) derived from MODIS images over the Arabian Gulf, Sea of Oman, and Arabian Sea. The considered atmospheric correction models have been used to derive MODIS normalized water-leaving radiances (nLw), which are compared to in situ water nLw(λ) data collected at different locations by Masdar Institute, United Arab of Emirates, and from AERONET-OC (the ocean color component of the Aerosol Robotic Network) database. From this comparison, the NIR model has been found to be the best performing model among the considered atmospheric correction models, which in turn shows disparity, especially at short wavelengths (400–500 nm) under high aerosol optical depth conditions (AOT (869) > 0.3) and over turbid waters. To reduce the error induced by these factors, a modified model taking into consideration the atmospheric and water turbidity conditions has been proposed. A turbidity index was used to identify the turbid water and a threshold of AOT (869) = 0.3 was used to identify the dusty atmosphere. Despite improved results in the MODIS nLw(λ) using the proposed approach, Chl-a models (OC3 and OC2) show low performance when compared to the in situ Chl-a measurements collected during several field campaigns organized by local, regional and international organizations. This discrepancy might be caused by the improper parametrization of these models or/and the improper selection of bands. Thus, an adaptive power fit algorithm (R2 = 0.95) has been proposed to improve the estimation of Chl-a concentration from 0.07 to 10 mg/m3 by using a new blue/red MODIS band ratio of (443,488)/645 instead of the default band ratio used for OC3(443,488)/547. The selection of this new band ratio (443,488)/645 has been based on using band 645 nm which has been found to represent both water turbidity and algal absorption. Numéro de notice : A2017-721 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2017.09.011 En ligne : https://doi.org/10.1016/j.isprsjprs.2017.09.011 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=88406
in ISPRS Journal of photogrammetry and remote sensing > vol 133 (November 2017) . - pp 46 - 60[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2017111 RAB Revue Centre de documentation En réserve L003 Disponible 081-2017112 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt 081-2017113 DEP-EXM Revue Saint-Mandé Dépôt en unité Exclu du prêt Real-time multi-GNSS single-frequency precise point positioning / Peter F. de Bakker in GPS solutions, vol 21 n° 4 (October 2017)PermalinkAssessing the performance of multi-GNSS precise point positioning in Asia-Pacific region / X. Zhao in Survey review, vol 49 n° 354 (September 2017)PermalinkInvestigation of automatic feature weighting methods (Fisher, Chi-square and Relief-F) for landslide susceptibility mapping / Emrehan Kutlug Sahin in Geocarto international, vol 32 n° 9 (September 2017)PermalinkPerformance evaluation of single-frequency point positioning with GPS, GLONASS, BeiDou and Galileo / L. Pan in Survey review, vol 49 n° 354 (September 2017)PermalinkSimultaneous extraction of roads and buildings in remote sensing imagery with convolutional neural networks / Rasha Alshehhi in ISPRS Journal of photogrammetry and remote sensing, vol 130 (August 2017)PermalinkPerformance evaluation of ionospheric time delay forecasting models using GPS observations at a low-latitude station / G. Sivavaraprasad in Advances in space research, vol 60 n° 2 (15 July 2017)PermalinkInteractive shearing for terrain visualization : an expert study / Jonas Buddeberg in Geoinformatica, vol 21 n° 3 (July - September 2017)PermalinkNew optimal smoothing scheme for improving relative and absolute accuracy of tightly coupled GNSS/SINS integration / Xiaohong Zhang in GPS solutions, vol 21 n° 3 (July 2017)PermalinkAn investigation into challenges experienced when route planning, navigating and wayfinding / Erin Koletsis in International journal of cartography, vol 3 n° 1 (June 2017)PermalinkPerformance evaluation of land change simulation models using landscape metrics / Sadeq Dezhkam in Geocarto international, vol 32 n° 6 (June 2017)Permalink