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Modeling and simulation of glacier avalanche: a case study of Gayari sector glaciers Hazards assessment / Muhammad Ashan Mahboob in IEEE Transactions on geoscience and remote sensing, vol 53 n° 11 (November 2015)
[article]
Titre : Modeling and simulation of glacier avalanche: a case study of Gayari sector glaciers Hazards assessment Type de document : Article/Communication Auteurs : Muhammad Ashan Mahboob, Auteur ; Javed Iqbal, Auteur ; Iqra Atif, Auteur Année de publication : 2015 Article en page(s) : pp 5824 - 5834 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] Afghanistan
[Termes IGN] ArcGIS
[Termes IGN] effondrement de terrain
[Termes IGN] énergie cinétique
[Termes IGN] estimation statistique
[Termes IGN] glacier
[Termes IGN] modélisation 3D
[Termes IGN] risque naturel
[Termes IGN] système d'information géographiqueRésumé : (Auteur) Glacier avalanches are natural hazards that could damage infrastructures and threaten lives in high-altitude mountainous terrains. On April 7, 2012, a massive ice avalanche struck a Pakistani base at Gayari sector, Saltoro Valley, and buried/killed 148 soldiers and civilians. Keeping in view the catastrophe, a study was designed with the objectives to: 1) model and simulate the Gayari sector glacier avalanche incident in terms of height, extent, velocity, pressure, and momentum; 2) generate hazard risk assessment of possible other glacier avalanches in the Saltoro Valley through modeling and simulation; and 3) suitability analysis of current camp sites and recommendation of new safe camps sites locations in the Saltoro valley. To simulate the Gayari sector glacier event and other Glacier possible avalanches, a physical process-based rapid mass movements (RAMMS) was used. The RAMMS has two main components, i.e., Voellmy-Salm (VS) model and random kinetic energy, which deals with variables such as avalanche height and the mean avalanche velocity during the course of simulation. The suitability analysis of current camp sites were achieved using weighted overlay analysis with different constraints in ArcGIS Spatial Analyst. The RAMMS model simulation of the Gayari avalanche event predicted a maximum velocity of 74 ms -1, generating a pressure of 5074 kPa and attaining a height of 45 m, whereas the predicted debris volume on the ground was 3.8145 million m 3. A good agreement was found between actual debris height and extent, as compared with the RAMMS model output. The RAMMS model simulated all the potential tributary glacier avalanches of Saltoro valley very well. The weighted overlay analyses in ArcGIS Spatial Analyst revealed that the existing camp sites are safe and were not threatened by the glacier avalanche hazard. However, it was recommended that the Gayari camp should not be constructed at the same location and should be relocated to the proposed safe camp sites identified in this research study. The proposed methodology developed in the current study could be applied in the Siachen conflict zone for avalanche hazard/risk analysis of all the camp sites located in the valley. Numéro de notice : A2015-773 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2419171 Date de publication en ligne : 15/06/2015 En ligne : https://doi.org/10.1109/TGRS.2015.2419171 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78829
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 11 (November 2015) . - pp 5824 - 5834[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015111 SL Revue Centre de documentation Revues en salle Disponible Particle filter-based estimation of inter-frequency phase bias for real-time GLONASS integer ambiguity resolution / Yumiao Tian in Journal of geodesy, vol 89 n° 11 (november 2015)
[article]
Titre : Particle filter-based estimation of inter-frequency phase bias for real-time GLONASS integer ambiguity resolution Type de document : Article/Communication Auteurs : Yumiao Tian, Auteur ; Maorong Ge, Auteur ; Frank Neitze, Auteur Année de publication : 2015 Article en page(s) : pp 1145-1158 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] ambiguïté entière
[Termes IGN] erreur systématique
[Termes IGN] phase GPS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïté
[Termes IGN] signal GLONASS
[Termes IGN] temps réel
[Termes IGN] variance de phase
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) GLONASS could hardly reach the positioning performance of GPS, especially for fast and real-time precise positioning. One of the reasons is the phase inter-frequency bias (IFB) at the receiver end prevents its integer ambiguity resolution. A number of studies were carried out to achieve the integer ambiguity resolution for GLONASS. Based on some of the revealed IFB characteristics, for instance IFB is a linear function of the received carrier frequency and L1 and L2 have the same IFB in unit of length, most of recent methods recommend estimating the IFB rate together with ambiguities. However, since the two sets of parameters are highly correlated, as demonstrated in previous studies, observations over several hours up to 1 day are needed even with simultaneous GPS observations to obtain a reasonable solution. Obviously, these approaches cannot be applied for real-time positioning. Actually, it can be demonstrated that GLONASS ambiguity resolution should also be available even for a single epoch if the IFB rate is precisely known. In addition, the closer the IFB rate value is to its true value, the larger the fixing RATIO will be. Based on this fact, in this paper, a new approach is developed to estimate the IFB rate by means of particle filtering with the likelihood function derived from RATIO. This approach is evaluated with several sets of experimental data. For both static and kinematic cases, the results show that IFB rates could be estimated precisely just with GLONASS data of a few epochs depending on the baseline length. The time cost with a normal PC can be controlled around 1 s and can be further reduced. With the estimated IFB rate, integer ambiguity resolution is available immediately and as a consequence, the positioning accuracy is improved significantly to the level of GPS fixed solution. Thus the new approach enables real-time precise applications of GLONASS. Numéro de notice : A2015-885 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0841-1 En ligne : https://doi.org/10.1007/s00190-015-0841-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79424
in Journal of geodesy > vol 89 n° 11 (november 2015) . - pp 1145-1158[article]Forest height estimation by means of Pol-InSAR data inversion : The role of the vertical wavenumber / Florian Kugler in IEEE Transactions on geoscience and remote sensing, vol 53 n° 10 (October 2015)
[article]
Titre : Forest height estimation by means of Pol-InSAR data inversion : The role of the vertical wavenumber Type de document : Article/Communication Auteurs : Florian Kugler, Auteur ; Seung-Kuk Lee, Auteur ; Irena Hajnsek, Auteur ; Konstantinos P. Papathanassiou, Auteur Année de publication : 2015 Article en page(s) : pp 5294 - 5311 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] données polarimétriques
[Termes IGN] estimation statistique
[Termes IGN] forêt
[Termes IGN] hauteur des arbres
[Termes IGN] image radar moirée
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] inversion
[Termes IGN] Pol-INSAR
[Termes IGN] polarimétrie radar
[Termes IGN] validation des donnéesRésumé : (Auteur) This paper examines the multifaceted effect of the effective spatial baseline, as expressed through the vertical (interferometric) wavenumber, on the inversion of forest height from polarimetric interferometric synthetic aperture radar (Pol-InSAR) data. First, the role of the vertical wavenumber in relating forest height to the interferometric (volume) coherence is introduced. Through the review of the forest height inversion from Pol-InSAR data, the effect of the vertical wavenumber on the inversion performance is evaluated. The selection of optimum with respect to forest height inversion performance, vertical wavenumbers is discussed. The impact of the acquisition geometry and terrain slopes on the vertical wavenumber and their consideration in the inversion methodology is addressed. The individual effects discussed are demonstrated by means of airborne repeat pass Pol-InSAR acquisitions in L- and P-band acquired over different forest conditions, including a boreal, a temperate, and a tropical forest test site. The achieved forest height inversion performance is validated against reference height data derived from airborne LIDAR acquisitions. Numéro de notice : A2015-747 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2420996 Date de publication en ligne : 04/05/2015 En ligne : https://doi.org/10.1109/TGRS.2015.2420996 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78755
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 10 (October 2015) . - pp 5294 - 5311[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015101 SL Revue Centre de documentation Revues en salle Disponible High-resolution forest canopy height estimation in an African blue carbon ecosystem / David Lagomasino in Remote sensing in ecology and conservation, vol 1 n° 1 (October 2015)
[article]
Titre : High-resolution forest canopy height estimation in an African blue carbon ecosystem Type de document : Article/Communication Auteurs : David Lagomasino, Auteur ; Temilola Fatoyinbo, Auteur ; Seung-Kuk Lee, Auteur ; Marc Simard, Auteur Année de publication : 2015 Article en page(s) : pp 51 - 60 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] biomasse
[Termes IGN] données localisées 3D
[Termes IGN] estimation statistique
[Termes IGN] hauteur des arbres
[Termes IGN] mangrove
[Termes IGN] MNS SRTM
[Termes IGN] MozambiqueRésumé : (auteur) Mangrove forests are one of the most productive and carbon dense ecosystems that are only found at tidally inundated coastal areas. Forest canopy height is an important measure for modeling carbon and biomass dynamics, as well as land cover change. By taking advantage of the flat terrain and dense canopy cover, the present study derived digital surface models (DSMs) using stereo-photogrammetric techniques on high-resolution spaceborne imagery (HRSI) for southern Mozambique. A mean-weighted ground surface elevation factor was subtracted from the HRSI DSM to accurately estimate the canopy height in mangrove forests in southern Mozambique. The mean and H100 tree height measured in both the field and with the digital canopy model provided the most accurate results with a vertical error of 1.18-1.84 m, respectively. Distinct patterns were identified in the HRSI canopy height map that could not be discerned from coarse shuttle radar topography mission canopy maps even though the mode and distribution of canopy heights were similar over the same area. Through further investigation, HRSI DSMs have the potential of providing a new type of three-dimensional dataset that could serve as calibration/validation data for other DSMs generated from spaceborne datasets with much larger global coverage. HSRI DSMs could be used in lieu of Lidar acquisitions for canopy height and forest biomass estimation, and be combined with passive optical data to improve land cover classifications. Numéro de notice : A2015--101 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1002/rse2.3 En ligne : http://doi.org/10.1002/rse2.3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=87170
in Remote sensing in ecology and conservation > vol 1 n° 1 (October 2015) . - pp 51 - 60[article]Documents numériques
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High-resolution forest canopy height estimation - pdf éditeurAdobe Acrobat PDF On diverse noises in hyperspectral unmixing / Chunzhi Li in IEEE Transactions on geoscience and remote sensing, vol 53 n° 10 (October 2015)
[article]
Titre : On diverse noises in hyperspectral unmixing Type de document : Article/Communication Auteurs : Chunzhi Li, Auteur ; Xiaohua Chen, Auteur ; Yunliang Jiang, Auteur Année de publication : 2015 Article en page(s) : pp 5388 - 5402 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse des mélanges spectraux
[Termes IGN] bruit (théorie du signal)
[Termes IGN] erreur aléatoire
[Termes IGN] factorisation de matrice non-négative
[Termes IGN] filtrage du bruit
[Termes IGN] image hyperspectraleRésumé : (Auteur) Traditional spectral unmixing methods are usually based on the linear mixture model (LMM) or nonlinear mixture model (NLMM), in which only the additive noise is considered. However, in hyperspectral applications, the additive, multiplicative, and mixed noises play important roles. In this paper, we propose an antinoise model for hyperspectral unmixing. In the antinoise model, all the additive, multiplicative and mixed noises are addressed. To deal with the problems faced by LMM or NLMM and to tackle the antinoise model, an antinoise model based hyperspectral unmixing method is presented, where block coordinate descent is employed to solve an approximated L0 norm constraint, then a nonnegative matrix factorization (NMF) method is presented, which is based on the bounded Itakura-Saito divergence. The experimental results on both synthetic and real hyperspectral data sets demonstrate the efficacy of the proposed model and the corresponding method. Numéro de notice : A2015-751 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2421993 Date de publication en ligne : 01/05/2015 En ligne : https://doi.org/10.1109/TGRS.2015.2421993 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78739
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 10 (October 2015) . - pp 5388 - 5402[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015101 SL Revue Centre de documentation Revues en salle Disponible Stochastic geometrical model and Monte Carlo optimization methods for building reconstruction from InSAR data / Yue Zhang in ISPRS Journal of photogrammetry and remote sensing, vol 108 (October 2015)PermalinkUnsupervised segmentation of high-resolution remote sensing images based on classical models of the visual receptive field / Miaozhong Xu in Geocarto international, vol 30 n° 9 - 10 (October - November 2015)PermalinkAnalysis of different methods for 3D reconstruction of natural surfaces from parallel-axes UAV images / Annette Eltner in Photogrammetric record, vol 30 n° 151 (September - November 2015)PermalinkAnalysis of a GNSS network using the theory of reliability for multiple outliers / M Mustafa Berber in Geodetski vestnik, vol 59 n° 3 (September - November 2015)PermalinkLes évolutions du PPP : l'apport d'une troisième fréquence pour réduire les temps de convergence / Denis Laurichesse in XYZ, n° 144 (septembre - novembre 2015)PermalinkMapping and assessing coastal resilience in the Caribbean region / Nina S.N. Lam in Cartography and Geographic Information Science, Vol 42 n° 4 (September 2015)PermalinkRecommendations 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)PermalinkReducing leakage error in GRACE-observed long-term ice mass change: a case study in West Antarctica / J. L. Chen in Journal of geodesy, vol 89 n° 9 (september 2015)PermalinkRelative orientation dependent on dual quaternions / Qing H. Sheng in Photogrammetric record, vol 30 n° 151 (September - November 2015)PermalinkA robust fixed rank kriging method for improving the spatial completeness and accuracy of satellite SST products / Yuxin Zhu in IEEE Transactions on geoscience and remote sensing, vol 53 n° 9 (September 2015)Permalink