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Assessment of VRS performances of the Algerian-CORS-network / Takka Elhadi in Bulletin des sciences géographiques, vol 27 n° 1 (2023)
[article]
Titre : Assessment of VRS performances of the Algerian-CORS-network Type de document : Article/Communication Auteurs : Takka Elhadi, Auteur ; Touabet Touabet, Auteur ; Boudrassene Abdennour, Auteur Année de publication : 2023 Article en page(s) : pp 25 - 33 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] affaiblissement géométrique de la précision
[Termes IGN] Algérie
[Termes IGN] disponibilité des données
[Termes IGN] intégrité des données
[Termes IGN] performance
[Termes IGN] précision du positionnement
[Termes IGN] répétabilité
[Termes IGN] réseau géodésique local
[Termes IGN] réseau géodésique permanent
[Termes IGN] station de référenceRésumé : (auteur) The Algerian Continuously Operating Reference Stations Network, so-called AL-CORS-Net, is deployed to provideNRTK services based onVRS method using Geo++GNSMART software.This paper investigates VRS performance in terms ofprecision, availability, integrity, Time-to-Fix-Ambiguity (TTFA), repeatability and PDOP.Several survey sessions were performed at different sites in the north of Algeria during October 2021 to January 2022. The results revealed good performance indicators; the precision was in the order of 1.3 cm in the horizontal component and about 2.2 cm in the vertical (at 1 sigma). The VRS solution's availability was 97.25%, its integrity was 98.8% in the horizontal and 94.9% in the vertical, and the TTFA ranged from a few seconds to a few minutes. The VRS measurements' repeatability presented similar measurement results throughout time. High satellite numbers have been tracked, their geometry (PDOP) was ideal. Numéro de notice : A2023-090 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : https://www.asjp.cerist.dz/en/downArticle/213/27/1/216928 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103152
in Bulletin des sciences géographiques > vol 27 n° 1 (2023) . - pp 25 - 33[article]Réservation
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Assessment of VRS performances ... - pdf éditeurAdobe Acrobat PDF Overview of methods and tools for evaluating future woody biomass availability in European countries / Susana Barreiro in Annals of Forest Science, vol 73 n° 4 (December 2016)
[article]
Titre : Overview of methods and tools for evaluating future woody biomass availability in European countries Type de document : Article/Communication Auteurs : Susana Barreiro, Auteur ; Mart-Jan Schelhaas, Auteur ; Gerald Kändler, Auteur ; Clara Antón-Fernández, Auteur ; Antoine Colin , Auteur ; Jean-Daniel Bontemps , Auteur ; Iciar A. Alberdi, Auteur ; Sonia Condés, Auteur ; Marius Dumitru, Auteur ; Angel Ferezliev, Auteur ; Christoph Fischer, Auteur ; Patrizia Gasparini, Auteur ; Thomas Gschwantner, Auteur ; Georg Kindermann, Auteur ; Bjarki Kjartansson, Auteur ; Pál Kovácsevics, Auteur ; Miloš Kučera, Auteur ; Anders Lundström, Auteur ; Gheorghe Marin, Auteur ; Gintautas Mozgeris, Auteur ; Thomas Nord-Larsen, Auteur ; Tuula Packalen, Auteur ; John Redmond, Auteur ; Sandro Sacchelli, Auteur ; Allan Sims, Auteur ; Arnór Snorrason, Auteur ; Nickola Stoyanov, Auteur ; Esther Thürig, Auteur ; Per-Erik Wikberg, Auteur Année de publication : 2016 Article en page(s) : pp Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] biomasse forestière
[Termes IGN] disponibilité des données
[Termes IGN] Europe (géographie politique)
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] modèle de simulation
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Context : Knowledge of realistic and sustainable wood availability in Europe is highly relevant to define climate change mitigation strategies at national and European level, to support the development of realistic targets for increased use of renewable energy sources and of industry wood. Future scenarios at European level highlight a deficit of domestic wood supply compared to wood consumption, and some European countries state they are harvesting above the increment.
Aims : Several country-level studies on wood availability have been performed for international reporting. However, it remains essential to improve the knowledge on the projection methods used across Europe to better evaluate forecasts.
Methods : Analysis was based on descriptions supplied by the national correspondents involved in USEWOOD COST Action (FP1001), and further enriched with additionaldata from international reports that allowed characterisation of the forests in these countries for the same base year.
Results : Methods currently used for projecting wood availability were described for 21 European countries. Projection systems based on National Forest Inventory (NFI) data prevail over methods based on forest management plans. Only a few countries lack nationwide projection tools, still using tools developed for specific areas.
Conclusions : A wide range of NFI-based systems for projecting wood availability exists, being under permanent improvement. The validation of projection forecasts and the inclusion of climate sensitive growth models into these tools are common aims for most countries. Cooperation among countries would result in higher efficiency when developing and improving projection tools and better comparability among them.Numéro de notice : A2016--087 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-016-0564-3 Date de publication en ligne : 17/06/2016 En ligne : http://doi.org/10.1007/s13595-016-0564-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84576
in Annals of Forest Science > vol 73 n° 4 (December 2016) . - pp[article]Plot location errors of National Forest Inventory: related factors and adverse effects on continuity of plot data / Haruki Nakajima in Journal of Forest Research, vol 21 n° 6 (December 2016)
[article]
Titre : Plot location errors of National Forest Inventory: related factors and adverse effects on continuity of plot data Type de document : Article/Communication Auteurs : Haruki Nakajima, Auteur Année de publication : 2016 Article en page(s) : pp 300 - 305 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] disponibilité des données
[Termes IGN] erreur de positionnement
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] Japon
[Termes IGN] placette d'échantillonnage
[Termes IGN] positionnement par GPS
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Plot location errors (distance between recorded and true coordinates) of National Forest Inventory (NFI) cause a mismatch between plot data and remotely sensed data and might prevent re-measurement because plots with large location errors are hard to find. However, few studies have examined the detailed distribution of errors and related factors, and no studies have verified whether the large errors prevent re-measurement. This study analyzed data related to 101 plots in central Japan that had been established by the First NFI (1999–2003) on a 4-km grid. Plot location errors of these plots were measured by revisiting. Selective Availability (SA) of the Global Positioning System, which degraded location accuracy until May 2000, was the most important factor in increasing plot location errors. The mean errors were 58.6 and 15.0 m, with and without SA, respectively. In 12 plots with large plot location errors (the mean error was 84.6 m), re-measurement in the Second NFI (2004–2008) was not conducted because plot locations could not be found. In these situations, alternative new plots were established; however, their species compositions were significantly different from the initial NFI plots. Plot location errors of NFI adversely affect the continuity of plot data as well as the analysis with remotely sensed data. Numéro de notice : A2016--074 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s10310-016-0538-1 Date de publication en ligne : 18/08/2016 En ligne : https://doi.org/10.1007/s10310-016-0538-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84444
in Journal of Forest Research > vol 21 n° 6 (December 2016) . - pp 300 - 305[article]Recommendations for the use of tree models to estimate national forest biomass and assess their uncertainty / Matieu Henry in Annals of Forest Science, vol 72 n° 6 (September 2015)
[article]
Titre : Recommendations for the use of tree models to estimate national forest biomass and assess their uncertainty Type de document : Article/Communication Auteurs : Matieu Henry, Auteur ; Miguel Cifuentes Jara, Auteur ; Maxime Réjou-Méchain, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 769 - 777 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] arbre (flore)
[Termes IGN] biomasse
[Termes IGN] disponibilité des données
[Termes IGN] estimation statistique
[Termes IGN] incertitude des données
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] masse végétale
[Termes IGN] sylviculture
[Termes IGN] volume (grandeur)Résumé : (auteur) Key message : Three options are proposed to improve the accuracy of national forest biomass estimates and decrease the uncertainty related to tree model selection depending on available data and national contexts.
Introduction : Different tree volume and biomass equations result in different estimates. At national scale, differences of estimates can be important while they constitute the basis to guide policies and measures, particularly in the context of climate change mitigation.
Method : Few countries have developed national tree volume and biomass equation databases and have explored its potential to decrease uncertainty of volume and biomasttags estimates. With the launch of the GlobAllomeTree webplatform, most countries in the world could have access to country-specific databases. The aim of this article is to recommend approaches for assessing tree and forest volume and biomass at national level with the lowest uncertainty. The article highlights the crucial need to link allometric equation development with national forest inventory planning efforts.
Results : Models must represent the tree population considered. Data availability; technical, financial, and human capacities; and biophysical context, among other factors, will influence the calculation process.
Conclusion : Three options are proposed to improve accuracy of national forest assessment depending on identified contexts. Further improvements could be obtained through improved forest stratification and additional non-destructive field campaigns.Numéro de notice : A2015-410 Affiliation des auteurs : non IGN Thématique : FORET/MATHEMATIQUE Nature : Article DOI : 10.1007/s13595-015-0465-x Date de publication en ligne : 20/03/2015 En ligne : https://doi.org/10.1007/s13595-015-0465-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76898
in Annals of Forest Science > vol 72 n° 6 (September 2015) . - pp 769 - 777[article]