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Atmospheric water vapor measurement in order to estimate continental precipitation over Algeria region based on the INCT-GNSS network / Abdellaoui Hassen in Bulletin des sciences géographiques, vol 27 n° 1 (2023)
[article]
Titre : Atmospheric water vapor measurement in order to estimate continental precipitation over Algeria region based on the INCT-GNSS network Type de document : Article/Communication Auteurs : Abdellaoui Hassen, Auteur ; Ali Omar Hammou, Auteur ; Soraya Makhlouf, Auteur ; Naima Zaourar, Auteur ; Mohamed Aïssa Meslem, Auteur Année de publication : 2023 Article en page(s) : pp 42 - 47 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Algérie
[Termes IGN] climat méditerranéen
[Termes IGN] données GNSS
[Termes IGN] données météorologiques
[Termes IGN] Méditerranée, mer
[Termes IGN] précipitation
[Termes IGN] teneur en vapeur d'eauRésumé : (auteur) Northern Algeria region is characterized a Mediterranean climate, cold, humid, dry winters and warm summers, same as other countries in the world, and is exposed to desertification problems. Along its coast, the average annual precipitation is 384 mm, so more than 75% of its territory has an annual precipitation lower than 384 mm. This is a global problem that affects a large number of people and land, and is now one of the most important environmental problems in Algeria. The work presented in this paper describe a preliminary study of GNSS meteorology technique based on GNSS positioning and estimation of the tropospheric water vapor quantity based exclusively on the INCT-GNSS network. According to our results, we noted that the integrated content of water vapor is a highly variable parameter that depends on the study region, in our study it is between the South and the North of Algeria, this variation is related to the geographical position in relation to the Mediterranean Sea, as well as the season, noticing that during the winter the quantities of water vapor are low compared to the summer. No relationship could be found between GNSS IWV and precipitation values, except for a significant increase in GNSS IWV that frequently precedes the arrival of precipitation. Improving atmospheric observation techniques and understanding of the key processes of precipitation formation is thus a major challenge for our society. In fact, a better prediction of precipitation would allow bettering anticipating the occurrence of floods and consequently to minimize the damages related to these events. Numéro de notice : A2023-091 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : https://www.asjp.cerist.dz/en/downArticle/213/27/1/216930 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103153
in Bulletin des sciences géographiques > vol 27 n° 1 (2023) . - pp 42 - 47[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 253-2023011 RAB Revue Centre de documentation En réserve L003 Disponible Documents numériques
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Atmospheric water vapor measurementAdobe Acrobat PDF Automatic detection of thin oil films on water surfaces in ultraviolet imagery / Ming Xie in Photogrammetric record, vol 38 n° 181 (March 2023)
[article]
Titre : Automatic detection of thin oil films on water surfaces in ultraviolet imagery Type de document : Article/Communication Auteurs : Ming Xie, Auteur ; Xiurui Zhang, Auteur ; Ying Li, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : pp 47 - 62 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] détection automatique
[Termes IGN] filtre optique
[Termes IGN] hydrocarbure
[Termes IGN] image AVIRIS
[Termes IGN] marée noire
[Termes IGN] niveau de gris (image)
[Termes IGN] rayonnement ultraviolet
[Termes IGN] segmentation d'image
[Termes IGN] seuillage binaire
[Termes IGN] surface de la merRésumé : (auteur) Among the various remote sensing technologies that have been applied to monitor oil spills on the sea surface, passive ultraviolet (UV) imaging is a controversial one that has raised some disputes in the community of oil spill remote sensing. As a result, the research and applications of oil spill detection using passive UV imaging have not been as developed as other methods. In order to clarify some existing questions on oil spill detection using passive UV remote sensing technology, this paper discusses the needs of thin oil film detection, examines the feasibility of thin oil film detection using passive UV imaging through field experiments under controlled conditions and validates it with the UV imagery derived from the airborne visible/infrared imaging spectrometer (AVIRIS) observation of the Deepwater Horizon oil spill. Two types of fully automatic models are designed to extract the thin oil films on the water surface: (1) a binary classification model based on an adaptive threshold; (2) an unsupervised image segmentation model based on image clustering and greyscale histogram analysis. The two models are tested on the UV imagery obtained through both field experiments and AVIRIS observations. The results indicate that the binary classification model can extract the thin oil films with reasonable accuracy under stable imaging conditions, while the unsupervised image clustering model can robustly detect the thin oil films at the cost of higher computational complexity. These results infer that passive UV imaging is an effective way to detect thin oil films and could be applied to provide early warning at the beginning stage of oil spills and reduce further damage. It may also be applied as a supplementary method for oil spill detection to achieve comprehensive oil spill monitoring. Numéro de notice : A2023-163 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/phor.12439 Date de publication en ligne : 09/02/2023 En ligne : https://doi.org/10.1111/phor.12439 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102866
in Photogrammetric record > vol 38 n° 181 (March 2023) . - pp 47 - 62[article]Brief communication: Glacier mapping and change estimation using very high-resolution declassified Hexagon KH-9 panoramic stereo imagery (1971-1984) / Sajid Ghuffar in The Cryosphere, vol 17 n° 3 (March 2023)
[article]
Titre : Brief communication: Glacier mapping and change estimation using very high-resolution declassified Hexagon KH-9 panoramic stereo imagery (1971-1984) Type de document : Article/Communication Auteurs : Sajid Ghuffar, Auteur ; Owen King, Auteur ; Grégoire Guillet, Auteur ; Ewelina Rupnik , Auteur ; Tobias Bolch, Auteur Année de publication : 2023 Article en page(s) : pp 1299 - 1306 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] glacier
[Termes IGN] image Corona
[Termes IGN] image panoramique
[Termes IGN] image Pléiades-HR
[Termes IGN] image SPOTRésumé : (auteur) The panoramic cameras (PCs) on board Hexagon KH-9 (KH-9PC) satellite missions from 1971–1984 captured very high-resolution stereo imagery with up to 60 cm spatial resolution. This study explores the potential of this imagery for glacier mapping and change estimation. We assess KH-9PC imagery using data from the KH-9 mapping camera (KH-9MC), KH-4PC, and SPOT and Pléiades satellite imagery. The high resolution of KH-9PC leads to higher-quality DEMs, which better resolve the accumulation region of the glaciers in comparison to the KH-9MC. On stable terrain, KH-9PC DEMs achieve an elevation accuracy of Numéro de notice : A2023-177 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/tc-17-1299-2023 Date de publication en ligne : 21/03/2023 En ligne : https://doi.org/10.5194/tc-17-1299-2023 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103285
in The Cryosphere > vol 17 n° 3 (March 2023) . - pp 1299 - 1306[article]Deriving map images of generalised mountain roads with generative adversarial networks / Azelle Courtial in International journal of geographical information science IJGIS, vol 37 n° 3 (March 2023)
[article]
Titre : Deriving map images of generalised mountain roads with generative adversarial networks Type de document : Article/Communication Auteurs : Azelle Courtial , Auteur ; Guillaume Touya , Auteur ; Xiang Zhang, Auteur Année de publication : 2023 Article en page(s) : pp 499 - 528 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse comparative
[Termes IGN] apprentissage dirigé
[Termes IGN] apprentissage non-dirigé
[Termes IGN] carte routière
[Termes IGN] données d'entrainement (apprentissage automatique)
[Termes IGN] généralisation cartographique automatisée
[Termes IGN] montagne
[Termes IGN] réseau antagoniste génératif
[Vedettes matières IGN] GénéralisationRésumé : (auteur) Map generalisation is a process that transforms geographic information for a cartographic at a specific scale. The goal is to produce legible and informative maps even at small scales from a detailed dataset. The potential of deep learning to help in this task is still unknown. This article examines the use case of mountain road generalisation, to explore the potential of a specific deep learning approach: generative adversarial networks (GAN). Our goal is to generate images that depict road maps generalised at the 1:250k scale, from images that depict road maps of the same area using un-generalised 1:25k data. This paper not only shows the potential of deep learning to generate generalised mountain roads, but also analyses how the process of deep learning generalisation works, compares supervised and unsupervised learning and explores possible improvements. With this experiment we have exhibited an unsupervised model that is able to generate generalised maps evaluated as good as the reference and reviewed some possible improvements for deep learning-based generalisation, including training set management and the definition of a new road connectivity loss. All our results are evaluated visually using a four questions process and validated by a user test conducted on 113 individuals. Numéro de notice : A2023-073 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2022.2123488 Date de publication en ligne : 20/10/2022 En ligne : https://doi.org/10.1080/13658816.2022.2123488 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101901
in International journal of geographical information science IJGIS > vol 37 n° 3 (March 2023) . - pp 499 - 528[article]Near real-time global ionospheric total electron content modeling and nowcasting based on GNSS observations / Xulei Jin in Journal of geodesy, vol 97 n° 3 (March 2023)
[article]
Titre : Near real-time global ionospheric total electron content modeling and nowcasting based on GNSS observations Type de document : Article/Communication Auteurs : Xulei Jin, Auteur ; Shuli Song, Auteur Année de publication : 2023 Article en page(s) : n° 27 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] carte ionosphérique mondiale
[Termes IGN] données Jason
[Termes IGN] modèle ionosphérique
[Termes IGN] temps réel
[Termes IGN] teneur totale en électrons
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) For the purposes of routinely providing reliable and low-latency Global Ionosphere Maps (GIMs), a method of estimating hourly updated near real-time GIM with a time latency of about 1–2 h based on a 24-h data sliding window of Global Navigation Satellite System (GNSS) near real-time observations and real-time data streams was presented. On the basis of the implementation of near real-time GIM estimation, an hourly updated GIM nowcasting method was further proposed to improve the accurate of short-term total electron content (TEC) prediction. We estimated the Shanghai Astronomical Observatory near real-time GIM (SHUG) and nowcasting GIM (SHPG) in the solar relatively active year (2014) and quiet year (2021), and employed GIMs provided by the International GNSS Service, the Global Positioning System (GPS) differential slant TECs (dSTECs) extracted from global independent GNSS stations, and the vertical TECs (VTECs) inverted from satellite altimetry as the references to validate the estimated results. The GPS dSTECs evaluation results show that SHUG behaves fairly consistent with the rapid GIMs, with a discrepancy of less than 1 TEC unit (TECu) overall. The standard deviations (STDs) of SHUG with respect to Jason-2/-3 VTECs are no more than 10% over the majority of rapid GIMs due to the instability of observations. The performance of 1-h nowcasting SHPG is significantlybetter than the Center for Orbit Determination in Europe (CODE) 1-day predicted GIM (C1PG). GPS dSTEC validation results indicate that 1-h nowcasting SHPG is 1 to 2 TECu more reliable than C1PG in eventful ionospheric electron activity regions, and it outperforms the C1PG by 10% overall versus Jason-2/-3 VTECs. The hourly updated SHUG and SHPG have relatively high reliability and low time latency, and thus can provide excellent service for (near) real-time users and offer more accurate TEC background information than daily predicted GIM for real-time GIM estimation. Numéro de notice : A2023-181 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-023-01715-3 Date de publication en ligne : 20/03/2023 En ligne : https://doi.org/10.1007/s00190-023-01715-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102950
in Journal of geodesy > vol 97 n° 3 (March 2023) . - n° 27[article]Species distribution modelling under climate change scenarios for maritime pine (Pinus pinaster Aiton) in Portugal / Cristina Alegria in Forests, vol 14 n° 3 (March 2023)PermalinkValidation of Island 3D-mapping based on UAV spatial point cloud optimization: a case study in Dongluo Island of China / Jian Wu in Photogrammetric Engineering & Remote Sensing, PERS, vol 89 n° 3 (March 2023)PermalinkTree species growth response to climate in mixtures of Quercus robur/Quercus petraea and Pinus sylvestris across Europe - a dynamic, sensitive equilibrium / Sonja Vospernik in Forest ecology and management, vol 530 (February-15 2023)PermalinkA GIS-based method for modeling methane emissions from paddy fields by fusing multiple sources of data / Linhua Ma in Science of the total environment, vol 859 n° 1 (February 2023)PermalinkAmazon forest spectral seasonality is consistent across sensor resolutions and driven by leaf demography / Nathan B. Gonçalves in ISPRS Journal of photogrammetry and remote sensing, vol 196 (February 2023)PermalinkForest structure and fine root biomass influence soil CO2 efflux in temperate forests under drought / Antonios Apostolakis in Forests, vol 14 n° 2 (February 2023)PermalinkA GIS-based flood risk mapping of Assam, India, using the MCDA-AHP approach at the regional and administrative level / Laxmi Gupta in Journal of maps, vol 18 n° 2 (February 2023)PermalinkTree growth, wood anatomy and carbon and oxygen isotopes responses to drought in Mediterranean riparian forests / J. Julio Camarero in Forest ecology and management, vol 529 (February-1 2023)PermalinkUndifferenced and uncombined GNSS time and frequency transfer with integer ambiguity resolution / Xiaolong Mi in Journal of geodesy, vol 97 n° 2 (February 2023)PermalinkGIS-based planning of buffer zones for protection of boreal streams and their riparian forests / Heikki Mykrä in Forest ecology and management, vol 528 (January-15 2023)Permalink