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Improving the quality of cartographic colour reproduction using the self-organizing map method / Mingguang Wu in Cartographic journal (the), Vol 55 n° 3 (August 2018)  

Public [article]  inCartographic journal (the) > Vol 55 n° 3 (August 2018) . - pp 273 - 284 Titre : Improving the quality of cartographic colour reproduction using the self-organizing map method Type de document : Article/Communication Auteurs : Mingguang Wu, Auteur ; A - Xing Zhu, Auteur ; Li He, Auteur Année de publication : 2018 Article en page(s) : pp 273 - 284 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie thématique [Termes IGN] carte de Kohonen [Termes IGN] carte thématique [Termes IGN] couleur (rédaction cartographique) [Termes IGN] couleur imprimée [Termes IGN] qualité cartographique [Termes IGN] représentation cartographique Résumé : (Auteur) Colour distortion, which is caused by the unavoidable mismatch between a map’s gamut and a device’s gamut, negatively affects the semiotic quality of maps. Cartographic communication often suffers from undesirable colour inconsistency. This method models cartographic colour reproduction as a constrained transform problem, namely, adapting a map’s gamut to fit a device’s gamut while preserving the semiotic quality. First, the characteristics of the map’s gamut are investigated by considering cartographic principles, and the fundamental concerns of preserving semiotic quality are proposed. Then, the self-organizing map method is introduced to iteratively optimize the cartographic colour reproduction. We implement this method and evaluate it based on a series of thematic maps. The results indicate that the proposed algorithm offers better results than two alternatives in terms of facilitating cartographic colour reproduction. Numéro de notice : A2018-519 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00087041.2017.1414106 Date de publication en ligne : 18/10/2018 En ligne : https://doi.org/10.1080/00087041.2017.1414106 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91325 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
030-2018031	RAB	Revue	Centre de documentation	En réserve L003	Disponible

Examining view angle effects on leaf N estimation in wheat using field reflectance spectroscopy / Xiao Song in ISPRS Journal of photogrammetry and remote sensing, vol 122 (December 2016)  

Public [article]  inISPRS Journal of photogrammetry and remote sensing > vol 122 (December 2016) . - pp 57 – 67 Titre : Examining view angle effects on leaf N estimation in wheat using field reflectance spectroscopy Type de document : Article/Communication Auteurs : Xiao Song, Auteur ; Wei Feng, Auteur ; Li He, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 57 – 67 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] angle de visée [Termes IGN] Canada [Termes IGN] Chine [Termes IGN] feuille (végétation) [Termes IGN] indice de végétation [Termes IGN] spectromètre imageur [Termes IGN] teneur en azote Résumé : (Auteur) Real-time, nondestructive monitoring of crop nitrogen (N) status is a critical factor for precision N management during wheat production. Over a 3-year period, we analyzed different wheat cultivars grown under different experimental conditions in China and Canada and studied the effects of viewing angle on the relationships between various vegetation indices (VIs) and leaf nitrogen concentration (LNC) using hyperspectral data from 11 field experiments. The objective was to improve the prediction accuracy by minimizing the effects of viewing angle on LNC estimation to construct a novel vegetation index (VI) for use under different experimental conditions. We examined the stability of previously reported optimum VIs obtained from 13 traditional indices for estimating LNC at 13 viewing zenith angles (VZAs) in the solar principal plane (SPP). Backscattering direction showed better index performance than forward scattering direction. Red-edge VIs including modified normalized difference vegetation index (mND705), ratio index within the red edge region (RI-1dB) and normalized difference red edge index (NDRE) were highly correlated with LNC, as confirmed by high R2 determination coefficients. However, these common VIs tended to saturation, as the relationships strongly depended on experimental conditions. To overcome the influence of VZA on VIs, the chlorophyll- and LNC-sensitive NDRE index was divided by the floating-position water band index (FWBI) to generate the integrated narrow-band vegetation index. The highest correlation between the novel NDRE/FWBI parameter and LNC (R2 = 0.852) occurred at −10°, while the lowest correlation (R2 = 0.745) occurred at 60°. NDRE/FWBI was more highly correlated with LNC than existing commonly used VIs at an identical viewing zenith angle. Upon further analysis of angle combinations, our novel VI exhibited the best performance, with the best prediction accuracy at 0° to −20° (R2 = 0.838, RMSE = 0.360) and relatively good accuracy at 0° to −30° (R2 = 0.835, RMSE = 0.366). As it is possible to monitor plant N status over a wide range of angles using portable spectrometers, viewing angles of as much as 0° to −30° are common. Consequently, we developed a united model across angles of 0° to −30° to reduce the effects of viewing angle on LNC prediction in wheat. The proposed combined NDRE/FWBI parameter, designated the wide-angle-adaptability nitrogen index (WANI), is superior for estimating LNC in wheat on a regional scale in China and Canada. Numéro de notice : A2016--021 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2016.10.002 En ligne : http://dx.doi.org/10.1016/j.isprsjprs.2016.10.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83884 [article]

An approach to transform Chinese historical books into scenario-based historical maps / Li He in Cartographic journal (the), vol 50 n° 1 (February 2013)  

Public [article]  inCartographic journal (the) > vol 50 n° 1 (February 2013) . - pp 49 - 65 Titre : An approach to transform Chinese historical books into scenario-based historical maps Type de document : Article/Communication Auteurs : Li He, Auteur ; Min Chen, Auteur ; Guonian Lu, Auteur Année de publication : 2013 Article en page(s) : pp 49 - 65 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie étrangère [Termes IGN] carte interactive [Termes IGN] cartographie historique [Termes IGN] Chine [Termes IGN] conception cartographique [Termes IGN] données spatiotemporelles [Termes IGN] histoire [Termes IGN] littérature [Termes IGN] monographie Résumé : (Auteur) Spatio-temporal information (e.g. time, location, person and event) recorded in detail in vast Chinese historical books can provide evidence about the movement of entities (e.g. people, family, army and weapons) and their underlying spatial behaviours. Furthermore, this information largely reflects the process of social development, which makes it valuable to both professional research and public awareness. However, this information cannot be easily expressed and visually utilized because it is often hidden in the text of historical books. Aiming to better realize the potential value of such abundant information derived from historical books and bridging the gap between historical research and geographic space, a feasible and appropriate approach is explored in this article, to guide the transforming process from historical books to historical maps. The hope is that providing the scenarios of historical events will benefit related historical and social research. First, the integral framework of the approach was introduced, and the detail of building the specific spatio-temporal framework for information matching was discussed. Based on the spatio-temporal framework, the specification for the representation of historical books was designed. By extracting the spatio-temporal data from historical books, organizing them according to the specification and matching them with the spatio-temporal framework, the scenarios of historical events in the book (e.g. wars, migration, diseases, natural disasters, mass movement, etc.) can be visually transformed into historical maps. As the most critical writing of the Chinese Twenty-Four Histories, the Records of the Grand Historian (also known as Shiji) was employed as an example to test the proposed approach. Numéro de notice : A2013-188 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/1743277412Y.0000000024 En ligne : https://doi.org/10.1179/1743277412Y.0000000024 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32326 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
030-2013011	RAB	Revue	Centre de documentation	En réserve L003	Disponible