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Assessing structural complexity of individual scots pine trees by comparing terrestrial laser scanning and photogrammetric point clouds / Noora Tienaho in Forests, Vol 13 n° 8 (August 2022)
[article]
Titre : Assessing structural complexity of individual scots pine trees by comparing terrestrial laser scanning and photogrammetric point clouds Type de document : Article/Communication Auteurs : Noora Tienaho, Auteur ; Tuomas Yrttimaa, Auteur ; Ville Kankare, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 1305 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] analyse comparative
[Termes IGN] Finlande
[Termes IGN] hauteur des arbres
[Termes IGN] image captée par drone
[Termes IGN] photogrammétrie aérienne
[Termes IGN] Pinus sylvestris
[Termes IGN] semis de points
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] structure-from-motion
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) Structural complexity of trees is related to various ecological processes and ecosystem services. To support management for complexity, there is a need to assess the level of structural complexity objectively. The fractal-based box dimension (Db) provides a holistic measure of the structural complexity of individual trees. This study aimed to compare the structural complexity of Scots pine (Pinus sylvestris L.) trees assessed with Db that was generated with point cloud data from terrestrial laser scanning (TLS) and aerial imagery acquired with an unmanned aerial vehicle (UAV). UAV imagery was converted into point clouds with structure from motion (SfM) and dense matching techniques. TLS and UAV measured Db-values were found to differ from each other significantly (TLS: 1.51 ± 0.11, UAV: 1.59 ± 0.15). UAV measured Db-values were 5% higher, and the range was wider (TLS: 0.81–1.81, UAV: 0.23–1.88). The divergence between TLS and UAV measurements was found to be explained by the differences in the number and distribution of the points and the differences in the estimated tree heights and number of boxes in the Db-method. The average point density was 15 times higher with TLS than with UAV (TLS: 494,000, UAV 32,000 points/tree), and TLS received more points below the midpoint of tree heights (65% below, 35% above), while UAV did the opposite (22% below, 78% above). Compared to the field measurements, UAV underestimated tree heights more than TLS (TLS: 34 cm, UAV: 54 cm), resulting in more boxes of Db-method being needed (4–64%, depending on the box size). Forest structure (two thinning intensities, three thinning types, and a control group) significantly affected the variation of both TLS and UAV measured Db-values. Still, the divergence between the two approaches remained in all treatments. However, TLS and UAV measured Db-values were consistent, and the correlation between them was 75%. Numéro de notice : A2022-652 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.3390/f13081305 Date de publication en ligne : 16/08/2022 En ligne : https://doi.org/10.3390/f13081305 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101499
in Forests > Vol 13 n° 8 (August 2022) . - n° 1305[article]Comparative analysis of real-time precise point positioning method in terms of positioning and zenith tropospheric delay estimation / Omer Faruk Atiz in Survey review, vol 55 n° 388 (January 2023)
[article]
Titre : Comparative analysis of real-time precise point positioning method in terms of positioning and zenith tropospheric delay estimation Type de document : Article/Communication Auteurs : Omer Faruk Atiz, Auteur ; Salih Alcay, Auteur ; Sermet Ogutcu, Auteur ; Ilkay Bugdayci, Auteur Année de publication : 2022 Article en page(s) : pp Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse comparative
[Termes IGN] positionnement ponctuel précis
[Termes IGN] retard troposphérique zénithal
[Termes IGN] RTKLIB
[Termes IGN] temps réelRésumé : (auteur) The positioning performance of widely used real-time precise point positioning (RT-PPP) software packages BNC, RTKLIB, and PPP-WIZARD were tested in terms of convergence time and accuracy. The convergence time of PPP-WIZARD solutions is reduced by ambiguity resolution (AR). The GPS + GLONASS + GALILEO (GRE) mode improved the convergence time of GPS + GALILEO (GE) mode by 22.0%, 15.5%, 17.1%, and 11.4% for the BNC, RTKLIB, PPP-WIZARD (AR) and PPP-WIZARD, respectively. For the GRE mode, RMSEs of the BNC, RTKLIB, PPP-WIZARD (AR), and PPP-WIZARD software packages in the horizontal/vertical component are 3.8/5.6, 2.6/6.2, 3.3/6.5, 4.3/7.0 cm, respectively. In comparison with the IGS-ZTD (International GNSS Service ZTD), BNC, RTKLIB, PPP-WIZARD (AR), and PPP-WIZARD solutions show a mean bias of 0.28, −0.72, 2.80, and 2.83 cm, respectively in GE mode. The GRE mode reduced the RMSEs of the ZTD estimations of BNC, RTKLIB, PPP-WIZARD (AR) and PPP-WIZARD by 2.9%, 5.1%, 0.6%, and 0.4% respectively. Numéro de notice : A2022-014 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/00396265.2021.2001627 Date de publication en ligne : 22/11/2021 En ligne : https://doi.org/10.1080/00396265.2021.2001627 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99089
in Survey review > vol 55 n° 388 (January 2023) . - pp[article]Full-waveform classification and segmentation-based signal detection of single-wavelength bathymetric LiDAR / Xue Ji in IEEE Transactions on geoscience and remote sensing, vol 60 n° 8 (August 2022)
[article]
Titre : Full-waveform classification and segmentation-based signal detection of single-wavelength bathymetric LiDAR Type de document : Article/Communication Auteurs : Xue Ji, Auteur ; Bisheng Yang, Auteur ; Yuan Wang, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 4208714 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] algorithme de Levenberg-Marquardt
[Termes IGN] analyse comparative
[Termes IGN] apprentissage automatique
[Termes IGN] classification par réseau neuronal convolutif
[Termes IGN] détection du signal
[Termes IGN] forme d'onde pleine
[Termes IGN] Hainan (Chine)
[Termes IGN] lidar bathymétrique
[Termes IGN] optimisation par essaim de particulesRésumé : (auteur) Single-wavelength bathymetric light detection and ranging (LiDAR) (532 nm) can provide seamless meter- and submeter-scale digital elevation model (DEMs) of both the terrestrial surface and seafloor. However, mixed terrestrial and bathymetric surfaces obtained by this sensor are challenging for full-waveform (FW) signal detection. This study addresses the issues in two FW mixed surfaces: accurate classification of terrestrial and nonterrestrial waveforms from the original waveforms without auxiliary information and flexible detection of peaks based on a new FW theoretical model. A novel FW signal detection model (FWSD) for single-wavelength bathymetric LiDAR is proposed without complex feature extraction and iterative procedure through waveform classification and segmentation. The raw FWs are divided into five categories for subsequent signal detection using a convolutional neural network that merges local descriptors with contextual information. The signal detection task is then split into FW segment recognition and peak extraction using a new FW model, which integrates a leapfrog sliding window FW segmentation, an improved extreme learning machine (ELM) algorithm for FW segment recognition, and a flexible signal detection framework. To search for the optimal initial parameters for ELM, a self-annealing particle swarm optimization (SAPSO) algorithm is introduced, and the output weight is adjusted by online sequence to improve its generalization. When combined with the Richardson–Lucy deconvolution (RLD) algorithm, FWSD can be adapted to deal with shallow water waveforms. Finally, a test demonstration with an airborne dataset shows that FWSD has higher detection efficiency and higher accuracy than Levenberg–Marquardt algorithm optimized generalized Gaussian model (LM-GGM) and RLD algorithm. Numéro de notice : A2022-661 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2022.3198168 Date de publication en ligne : 11/08/2022 En ligne : https://doi.org/10.1109/TGRS.2022.3198168 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101517
in IEEE Transactions on geoscience and remote sensing > vol 60 n° 8 (August 2022) . - n° 4208714[article]Ground surface elevation changes over permafrost areas revealed by multiple GNSS interferometric reflectometry / Yufeng Hu in Journal of geodesy, vol 96 n° 8 (August 2022)
[article]
Titre : Ground surface elevation changes over permafrost areas revealed by multiple GNSS interferometric reflectometry Type de document : Article/Communication Auteurs : Yufeng Hu, Auteur ; Ji Wang, Auteur ; Zhenhong Li, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 56 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Alaska (Etats-Unis)
[Termes IGN] analyse diachronique
[Termes IGN] dégel
[Termes IGN] données Galileo
[Termes IGN] données GLONASS
[Termes IGN] pergélisol
[Termes IGN] rapport signal sur bruit
[Termes IGN] réflecteur
[Termes IGN] réflectométrie par GNSS
[Termes IGN] signal GNSS
[Termes IGN] surface du sol
[Termes IGN] variation saisonnièreRésumé : (auteur) Ground subsidence and uplift caused by the annual thawing and freezing of the active layer are important variables in permafrost studies. Global positioning system interferometric reflectometry (GPS-IR) has been successfully applied to retrieve the continuous ground surface movements in permafrost areas. However, only GPS signals were used in previous studies. In this study, using multiple global navigation satellite system (GNSS) signal-to-noise ratio (SNR) observations recorded by a GNSS station SG27 in Utqiaġvik, Alaska during the period from 2018 to 2021, we applied multiple GNSS-IR (multi-GNSS-IR) technique to the SNR data and obtained the complete and continuous ground surface elevation changes over the permafrost area at a daily interval in snow-free seasons in 2018 and 2019. The GLONASS-IR and Galileo-IR measurements agreed with the GPS-IR measurements at L1 frequency, which are the most consistent measurements among all multi-GNSS measurements, in terms of the overall subsidence trend but clearly showed periodic noises. We proposed a method to reconstruct the GLONASS- and Galileo-IR elevation changes by specifically grouping and fitting them with a composite model. Compared with GPS L1 results, the unbiased root mean square error (RMSE) of the reconstructed Galileo measurements reduced by 50.0% and 42.2% in 2018 and 2019, respectively, while the unbiased RMSE of the reconstructed GLONASS measurements decreased by 41.8% and 25.8% in 2018 and 2019, respectively. Fitting the composite model to the combined multi-GNSS-IR, we obtained seasonal displacements of − 3.27 ± 0.13 cm (R2 = 0.763) and − 10.56 ± 0.10 cm (R2 = 0.912) in 2018 and 2019, respectively. Moreover, we found that the abnormal summer heave was strongly correlated with rain events, implying hydrological effects on the ground surface elevation changes. Our study shows the feasibility of multi-GNSS-IR in permafrost areas for the first time. Multi-GNSS-IR opens up a great opportunity for us to investigate ground surface movements over permafrost areas with multi-source observations, which are important for our robust analysis and quantitative understanding of frozen ground dynamics under climate change. Numéro de notice : A2022-606 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-022-01646-5 Date de publication en ligne : 13/08/2022 En ligne : https://doi.org/10.1007/s00190-022-01646-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101385
in Journal of geodesy > vol 96 n° 8 (August 2022) . - n° 56[article]Influence of the declaration of protected natural areas on the evolution of forest fires in collective lands in Galicia (Spain) / Gervasio Lopez Rodriguez in Forests, Vol 13 n° 8 (August 2022)
[article]
Titre : Influence of the declaration of protected natural areas on the evolution of forest fires in collective lands in Galicia (Spain) Type de document : Article/Communication Auteurs : Gervasio Lopez Rodriguez, Auteur ; Veronica Rodriguez vicente, Auteur ; Manuel F. Marey-Pérez, Auteur Année de publication : 2022 Article en page(s) : n° 1161 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse diachronique
[Termes IGN] Eucalyptus globulus
[Termes IGN] forêt privée
[Termes IGN] Galice (Espagne)
[Termes IGN] incendie de forêt
[Termes IGN] Pinus pinaster
[Termes IGN] protection des forêts
[Termes IGN] Quercus pedunculata
[Termes IGN] site Natura 2000
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Since the adoption of European Union Council Directive 92/43 on the conservation of natural habitats and wild fauna and flora, some opposition has arisen among owners and managers of land affected by the directive. Some studies have indicated that some of this opposition has found expression in subsequent arson fires in these areas. This article analyses the occurrence of arson fires in the SACs (Special Areas of Conservation) included in the European ecological network, Natura 2000, in Galicia (Spain), more specifically in the montes vecinales en mano común (MVMCs), which are privately owned collective lands. We tested whether the declaration of SACs had a statistical impact on the forest fire regime in the period 1999–2014. The analyses focused on the sub-periods of 1999–2004 and 2005–2014, i.e., before and after the approval of the list of sites of community importance in the study area in December 2004. The results obtained show that, after the declaration of protection, there was a statistically significant increase in the area burnt by fire in these areas, mainly on private estates. We also found that the percentage of arson fires after 2004 was higher in SACs than in other territorial units. We found that the percentage of arson fires was reduced less in SACs than in other territorial units. Furthermore, we found that the area burnt per fire after 2004 in SACs was almost double that in the MVMC-SACs (12.04 ha versus 6.64 ha), so it can be concluded that the conservationist policies of the Natura 2000 network in Galicia have not had a positive effect on the forest fire regime. Numéro de notice : A2022-653 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.3390/f13081161 Date de publication en ligne : 22/07/2022 En ligne : https://doi.org/10.3390/f13081161 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101501
in Forests > Vol 13 n° 8 (August 2022) . - n° 1161[article]Measuring COVID-19 vulnerability for Northeast Brazilian municipalities: Social, economic, and demographic factors based on multiple criteria and spatial analysis / Ciro José Jardim De Figueiredo in ISPRS International journal of geo-information, vol 11 n° 8 (August 2022)PermalinkPositioning performance of GNSS-PPP and PPP-AR methods for determining the vertical displacements / Burak Akpinar in Survey review, vol 55 n° 388 (January 2023)PermalinkRemote sensing and phytoecological methods for mapping and assessing potential ecosystem services of the Ouled Hannèche Forest in the Hodna Mountains, Algeria / Amal Louail in Forests, Vol 13 n° 8 (August 2022)PermalinkTracking annual dynamics of mangrove forests in mangrove National Nature Reserves of China based on time series Sentinel-2 imagery during 2016–2020 / Rong Zhang in International journal of applied Earth observation and geoinformation, vol 112 (August 2022)PermalinkA comparison of three multi-criteria decision-making models in mapping flood hazard areas of Northeast Penang, Malaysia / Rofiat Bunmi Mudashiru in Natural Hazards, vol 112 n° 3 (July 2022)PermalinkDetermination of vertical land movements through the integration of tide gauge observations and satellite altimetry data at the Brazilian Vertical Datum from 2002 to 2015 / Samoel Gehl in Boletim de Ciências Geodésicas, vol 28 n° 2 ([01/07/2022])PermalinkEvaluation of the GSRM2.1 and the NUVEL1-A values in Europe using SLR and VLBI based geodetic velocity fields / Mina Rahmani in Survey review, vol 54 n° 385 (July 2022)PermalinkGlobal forecasting of ionospheric vertical total electron contents via ConvLSTM with spectrum analysis / Jinpei Chen in GPS solutions, vol 26 n° 3 (July 2022)PermalinkModelling areas for sustainable forest management in a mining and human dominated landscape: A Geographical Information System (GIS)- Multi-Criteria Decision Analysis (MCDA) approach / Xavier Takam Tiamgne in Annals of GIS, vol 28 n° 3 (July 2022)PermalinkRisk assessment and prediction of forest health for effective geo-environmental planning and monitoring of mining affected forest area in hilltop region / Narayan Kayet in Geocarto international, vol 37 n° 11 ([15/06/2022])Permalink