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Titre : Open mapping towards sustainable development goals : Voices of youthmappers on community engaged scholarship Type de document : Monographie Auteurs : Patricia Solís, Éditeur scientifique ; Marcela Zeballos, Éditeur scientifique Editeur : Springer Nature Année de publication : 2023 Importance : 382 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-3-031-05182-1 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique web
[Termes IGN] Afrique occidentale
[Termes IGN] approche participative
[Termes IGN] Asie (géographie politique)
[Termes IGN] cartographe
[Termes IGN] cartographie thématique
[Termes IGN] catastrophe naturelle
[Termes IGN] changement climatique
[Termes IGN] développement durable
[Termes IGN] données localisées
[Termes IGN] eau
[Termes IGN] édition en libre accès
[Termes IGN] formation
[Termes IGN] géopolitique
[Termes IGN] OpenStreetMap
[Termes IGN] universitéRésumé : (éditeur) This collection amplifies the experiences of some of the world’s young people who are working to address SDGs using geospatial technologies and multi-national collaboration. Authors from every region of the world who have emerged as leaders in the YouthMappers movement share their perspectives and knowledge in an accessible and peer-friendly format. YouthMappers are university students who create and use open mapping for development and humanitarian purposes. Their work leverages digital innovations - both geospatial platforms and communications technologies - to answer the call for leadership to address sustainability challenges. The book conveys a sense of robust knowledge emerging from formal studies or informal academic experiences - in the first-person voices of students and recent graduates who are at the forefront of creating a new map of the world. YouthMappers use OpenStreetMap as the foundational sharing mechanism for creating data together. Authors impart the way they are learning about themselves, about each other, about the world. They are developing technology skills, and simultaneously teaching the rest of the world about the potential contributions of a highly connected generation of emerging world leaders for the SDGs. The book is timely, in that it captures a pivotal moment in the trajectory of the YouthMappers movement’s ability to share emerging expertise, and one that coincides with a pivotal moment in the geopolitical history of planet earth whose inhabitants need to hear from them. Most volumes that cover the topic of sustainability in terms of youth development are written by non-youth authors. Moreover, most are written by non-majoritarian, entrenched academic scholars. This book instead puts forward the diverse voices of students and recent graduates in countries where YouthMappers works, all over the world. Authors cover topics that range from water, agriculture, food, to waste, education, gender, climate action and disasters from their own eyes in working with data, mapping, and humanitarian action, often working across national boundaries and across continents. To inspire readers with their insights, the chapters are mapped to the United Nations 17 Sustainable Development Goals (SDGs) in ways that connect a youth agenda to a global agenda. With a preface written by Carrie Stokes, Chief Geographer and GeoCenter Director, United States Agency for International Development (USAID). This is an open access book. Note de contenu : 1- Introduction
Part I- Mapping for the goals on poverty, hunger, health, education, gender, water, and energy
2- Open data addressing challenges associated with informal settlements in the global South
3- Leveraging spatial technology for agricultural intensification to address hunger in Ghana
4- Rural household food insecurity and child malnutrition in Northern Ghana
5- Where is the closest health clinic? YouthMappers map their communities before and during the COVID-19 pandemic
6- Cross-continental youthmappers action to fight schistosomiasis transmission in Senegal
7- Understanding youthmappers’ contributions to building resilient communities in Asia
8- Activating education for sustainable development goals through youthmappers
9- Seeing the world through maps: An inclusive and youth-oriented approach
10- Youth engagement and the water–energy–land nexus in Costa Rica
11- Power grid mapping in West Africa
12- Mapping access to electricity in urban and rural Nigeria
Part II- Youth action on work, leadership, innovation, inequality, cities, production and land
13- Stories from students building sustainability through transfer of leadership
14- Drones for good: Mapping out the SDGs using innovative technology in Malawi
15- Assessing youthmappers contributions to the generation of open geospatial data in Africa
16- Mapping invisible and inaccessible areas of Brazilian cities to reduce inequalities
17- Visualizing youthMappers’ contributions to environmental resilience in Latin AmericaNuméro de notice : 24082 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Recueil / ouvrage collectif DOI : 10.1007/978-3-031-05182-1 En ligne : https://doi.org/10.1007/978-3-031-05182-1 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102333 Détection des forêts dégradées en Guinée à partir des images satellites Sentinel-2 : évaluation de l'apport potentiel des nouveaux capteurs satellitaires optiques et radars / An Vo Quang in Blog de la RFPT, sans n° ([11/10/2021])
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Titre : Détection des forêts dégradées en Guinée à partir des images satellites Sentinel-2 : évaluation de l'apport potentiel des nouveaux capteurs satellitaires optiques et radars Type de document : Article/Communication Auteurs : An Vo Quang, Auteur Année de publication : 2021 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Afrique occidentale
[Termes IGN] apprentissage profond
[Termes IGN] classification dirigée
[Termes IGN] dégradation de l'environnement
[Termes IGN] dégradation de la flore
[Termes IGN] détection automatique
[Termes IGN] forêt alpestre
[Termes IGN] Guinée
[Termes IGN] image Sentinel-MSI
[Termes IGN] photo-interprétation
[Termes IGN] série temporelleRésumé : (Auteur) [Contexte] Les travaux de la thèse CIFRE ont été réalisés dans le cadre d'un partenariat entre l'Institut interdisciplinaire de recherche en énergie de Paris (LIED) et IGN FI, une société d'ingénierie géographique (partenaire export de l'IGN - Institut national de l’information géographique et forestière) qui réalise des projets sur tous les continents et dans tous les domaines d'application de la géomatique, notamment l'aménagement du territoire, l'environnement, l'agriculture, l'administration foncière ou la gestion des risques. Plus spécifiquement, les travaux de thèse se sont intégrés au projet de Zonage Agro-Ecologique de Guinée (ZAEG) coordonné par IGN FI et financé par l'Agence Française de Développement (AFD) pour le ministère de l’Agriculture de Guinée. Contrairement à la déforestation, la dégradation forestière implique un changement de la structure forestière sans modification de l'utilisation du sol. Ce changement est subtil et moins visible que la déforestation. La dégradation des forêts est une préoccupation majeure car un potentiel de séquestration du carbone est perdu. Ce phénomène varie en fonction de l'emplacement géographique, des facteurs anthropiques, du climat, des types de forêts impactées, donc il n'existe pas de méthodologie de détection unique pour cartographier la dégradation des forêts à l'échelle mondiale. En Guinée, le principal processus de dégradation est l'exploitation forestière sélective dans la forêt de massif, en plus de la fragmentation de la forêt causée par le changement d'utilisation des terres. L’objectif est d’optimiser les méthodes de photo-interprétation utilisées par IGN FI pour détecter les zones de forêt dégradée. Le suivi du couvert forestier à l'aide des méthodes traditionnelles de télédétection nécessite un coût important en termes d'expertise en photo-interprétation. Nous proposons une approche de suivi par une procédure de classification semi-automatisée avec un coût de photo-interprétation minimum en incluant le contexte pixellaire, en intégrant les données du capteur Sentinel-2, acquises de manière répétitive. Numéro de notice : A2021-679 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : sans Date de publication en ligne : 11/10/2021 En ligne : https://rfpt-sfpt.github.io/blog/sentinel-2/s%C3%A9rie%20temporelle/deep%20learn [...] Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99040
in Blog de la RFPT > sans n° [11/10/2021][article]Performance evaluation of artificial neural networks for natural terrain classification / Perpetual Hope Akwensi in Applied geomatics, vol 13 n° 1 (May 2021)
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Titre : Performance evaluation of artificial neural networks for natural terrain classification Type de document : Article/Communication Auteurs : Perpetual Hope Akwensi, Auteur ; Eric Thompson Brantson, Auteur ; Johanna Ngula Niipele, Auteur ; et al., Auteur Année de publication : 2021 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Afrique occidentale
[Termes IGN] classification par nuées dynamiques
[Termes IGN] échantillonnage
[Termes IGN] fonction de base radiale
[Termes IGN] image Landsat-OLI
[Termes IGN] image multibande
[Termes IGN] inventaire de la végétation
[Termes IGN] réalité de terrain
[Termes IGN] regroupement de données
[Termes IGN] réseau neuronal artificiel
[Termes IGN] segmentation d'imageRésumé : (auteur) Remotely sensed image segmentation and classification form a very important part of remote sensing which involves geo-data processing and analysis. Artificial neural networks (ANNs) are powerful machine learning approaches that have been successfully implemented in numerous fields of study. There exist many kinds of neural networks and there is no single efficient approach for resolving all geospatial problems. Therefore, this research aims at investigating and evaluating the efficiency of three ANN approaches, namely, backpropagation neural network (BPNN), radial basis function neural network (RBFNN), and Elman backpropagation recurrent neural network (EBPRNN) using multi-spectral satellite images for terrain feature classification. Additionally, there has been close to no application of EBPRNN in modeling multi-spectral satellite images even though they also contain patterns. The efficiency of the three tested approaches is presented using the kappa coefficient, user’s accuracy, producer’s accuracy, overall accuracy, classification error, and computational simulation time. The study demonstrated that all the three ANN models achieved the aim of pattern identification, segmentation, and classification. This paper also discusses the observations of increasing sample sizes as inputs in the various ANN models. It was concluded that RBFNN’s computational time increases with increasing sample size and consequently increasing the number of hidden neurons; BPNN on overall attained the highest accuracy compared to the other models; EBPRNN’s accuracy increases with increasing sample size, hence a promising and perhaps an alternative choice to BPNN and RBFNN if very large datasets are involved. Based on the performance metrics used in this study, BPNN is the best model out of the three evaluated ANN models. Numéro de notice : A2021-223 Affiliation des auteurs : non IGN Thématique : IMAGERIE/INFORMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s12518-021-00360-9 Date de publication en ligne : 13/02/2021 En ligne : https://doi.org/10.1007/s12518-021-00360-9 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97194
in Applied geomatics > vol 13 n° 1 (May 2021)[article]Using Ranked Probability Skill Score (RPSS) as Nonlocal Root-Mean-Square Errors (RMSEs) for Mitigating Wet Bias of Soil Moisture Ocean Salinity (SMOS) Soil Moisture / Ju Hyoung Lee in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 2 (February 2020)
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Titre : Using Ranked Probability Skill Score (RPSS) as Nonlocal Root-Mean-Square Errors (RMSEs) for Mitigating Wet Bias of Soil Moisture Ocean Salinity (SMOS) Soil Moisture Type de document : Article/Communication Auteurs : Ju Hyoung Lee, Auteur Année de publication : 2020 Article en page(s) : pp 91 - 98 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Afrique occidentale
[Termes IGN] données multitemporelles
[Termes IGN] erreur moyenne quadratique
[Termes IGN] erreur systématique
[Termes IGN] humidité du sol
[Termes IGN] image SMOS
[Termes IGN] salinitéRésumé : (Auteur) To mitigate instantaneously evolving biases in satellite retrievals, a stochastic approach is applied over West Africa. This stochastic approach independently self-corrects Soil Moisture Ocean Salinity (SMOS) wet biases, unlike the cumulative density function (CDF) matching that rescales satellite retrievals with respect to several years of reference data. Ranked probability skill score (RPSS) is used as nonlocal root-mean-square errors (RMSEs) to assess stochastic retrievals. Stochastic method successfully decreases RMSEs from 0.146 m3/m3 to 0.056 m3/m3 in the Republic of Benin and from 0.080 m3/m3 to 0.038 m3/m3 in Niger, while the CDF matching method exacerbates the original SMOS biases up to 0.141 m3/m3 in Niger, and 0.120 m3/m3 in Benin. Unlike the CDF matching or European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA))–interim soil moisture, only a stochastic retrieval responds to Tropical Rainfall Measuring Mission rainfall. Based on the effects of bias correction, RPSS is suggested as a nonlocal verification without needing local measurements. Numéro de notice : A2020-126 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14358/PERS.86.2.91 Date de publication en ligne : 01/02/2020 En ligne : https://doi.org/10.14358/PERS.86.2.91 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94772
in Photogrammetric Engineering & Remote Sensing, PERS > vol 86 n° 2 (February 2020) . - pp 91 - 98[article]Sensitivity of GPS tropospheric estimates to mesoscale convective systems in West Africa / Samuel Nahmani in Atmospheric chemistry and physics, vol 19 n° 14 (July 2019)
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Titre : Sensitivity of GPS tropospheric estimates to mesoscale convective systems in West Africa Type de document : Article/Communication Auteurs : Samuel Nahmani , Auteur ; Olivier Bock
, Auteur ; Françoise Guichard, Auteur
Année de publication : 2019 Projets : VEGAN / Bock, Olivier, TOSCA / Bock, Olivier Article en page(s) : pp 9541 - 9561 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] Afrique occidentale
[Termes IGN] analyse de sensibilité
[Termes IGN] bande C
[Termes IGN] convection
[Termes IGN] données GPS
[Termes IGN] GAMIT
[Termes IGN] GIPSY-OASIS
[Termes IGN] gradient de troposphère
[Termes IGN] meso échelle
[Termes IGN] modèle atmosphérique
[Termes IGN] Niger
[Termes IGN] propagation troposphérique
[Termes IGN] résidu
[Termes IGN] retard troposphérique zénithal
[Termes IGN] signal GPSRésumé : (Auteur) This study analyzes the characteristics of GPS tropospheric estimates (zenith wet delays – ZWDs, gradients, and post-fit phase residuals) during the passage of mesoscale convective systems (MCSs) and evaluates their sensitivity to the research-level GPS data processing strategy implemented. Here, we focus on MCS events observed during the monsoon season of West Africa. This region is particularly well suited for the study of these events due to the high frequency of MCS occurrences in the contrasting climatic environments between the Guinean coast and the Sahel. This contrast is well sampled with data generated by six African Monsoon Multidisciplinary Analysis (AMMA) GPS stations. Tropospheric estimates for a 3-year period (2006–2008), processed with both the GAMIT and GIPSY-OASIS software packages, were analyzed and intercompared. First, the case of a MCS that passed over Niamey, Niger, on 11 August 2006 demonstrates a strong impact of the MCS on GPS estimates and post-fit residuals when the GPS signals propagate through the convective cells as detected on reflectivity maps from the MIT C-band Doppler radar. The estimates are also capable of detecting changes in the structure and dynamics of the MCS. However, the sensitivity is different depending on the tropospheric modeling approach adopted in the software. With GIPSY-OASIS, the high temporal sampling (5 min) of ZWDs and gradients is well suited for detecting the small-scale, short-lived, convective cells, while the post-fit residuals remain quite small. With GAMIT, the lower temporal sampling of the estimated parameters (hourly for ZWDs and daily for gradients) is not sufficient to capture the rapid delay variations associated with the passage of the MCS, but the post-fit phase residuals clearly reflect the presence of a strong refractivity anomaly. The results are generalized with a composite analysis of 414 MCS events observed over the 3-year period at the six GPS stations with the GIPSY-OASIS estimates. A systematic peak is found in the ZWDs coincident with the cold pool crossing time associated with the MCSs. The tropospheric gradients reflect the path of the MCS propagation (generally from east to west). This study concludes that ZWDs, gradients, and post-fit phase residuals provide relevant and complementary information on MCSs passing over or in the vicinity of a GPS station. Numéro de notice : A2019-572 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/acp-19-9541-2019 Date de publication en ligne : 29/07/2019 En ligne : https://doi.org/10.5194/acp-19-9541-2019 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94444
in Atmospheric chemistry and physics > vol 19 n° 14 (July 2019) . - pp 9541 - 9561[article]PermalinkMapping and estimating land change between 2001 and 2013 in a heterogeneous landscape in West Africa: Loss of forestlands and capacity building opportunities / Hèou Maléki Badjana in International journal of applied Earth observation and geoinformation, vol 63 (December 2017)
PermalinkLe cycle de l'eau dans le système de mousson d'Afrique de l'Ouest / Christophe Peugeot in La Météorologie, n° spéc (octobre 2012)
PermalinkCartographie et participation pour la coopération environnementale : le terrain et la restitution des savoirs traditionnels en Afrique subsaharienne / F. Burini in Annales de géographie, n° 687 - 688 (septembre - décembre 2012)
PermalinkLand water storage changes from ground and space geodesy : first results from the GHYRAF (Gravity and Hydrology in Africa) experiment / Jacques Hinderer in Pure and applied geophysics, vol 169 n° 8 (August 2012)
PermalinkHydrological deformation induced by the West African Monsoon : Comparison of GPS, GRACE and loading models / Samuel Nahmani in Journal of geophysical research : Solid Earth, Vol 117 n° B5 (May 2012)
PermalinkMéthodologies en traitement de données GPS pour les sciences de l’environnement / Samuel Nahmani (2012)
PermalinkL'apport des données GPS AMMA pour l'étude du cycle de l'eau de la mousson africaine / Olivier Bock in Bulletin d'information scientifique et technique de l'IGN, n° 77 (avril 2011)
PermalinkMesoscale water cycle within the West African Monsoon / Christophe Peugeot in Atmospheric Science Letters, vol 12 n° 1 (January - March 2011)
PermalinkOperational meteorology in West Africa : observational networks, weather analysis and forecasting / Andreas H. Fink in Atmospheric Science Letters, vol 12 n° 1 (January - March 2011)
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