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Auteur Z. Li |
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A robust weighted total least-squares solution with Lagrange multipliers / X. Gong in Survey review, vol 49 n° 354 (September 2017)
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[article]
Titre : A robust weighted total least-squares solution with Lagrange multipliers Type de document : Article/Communication Auteurs : X. Gong, Auteur ; Z. Li, Auteur Année de publication : 2017 Article en page(s) : pp 176 - 185 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse numérique
[Termes IGN] méthode des moindres carrés
[Termes IGN] méthode robuste
[Termes IGN] pondération
[Termes IGN] régression
[Termes IGN] régression linéaire
[Termes IGN] transformation de coordonnéesRésumé : (Auteur) Weighted total least-squares (WTLS) is becoming popular for parameter estimations in geodesy and surveying. However, it does not take into consideration the possible gross errors in observations, which may lead to a reduction in the robustness and reliability of parameter estimations. In order to solve this problem, in this study, Lagrange multipliers (LM) are employed to make WTLS solution rigorous and the IGG (Institute of Geodesy and Geophysics) weight function is employed to make WTLS solution more robust and reliable, resulting in a new robust WTLS solution (RWTLS-LM-IGG). A comparison with existing WTLS and robust WTLS solutions is conducted for linear regression and coordinate transformation, through experimental evaluation with simulation data sets (with different numbers and magnitudes of gross errors) and two sets of real-life data. The results of simulation experiments show that the variance component and the mean square error of estimated parameter vector obtained by using the existing methods increase almost linearly with an increase in the numbers and magnitudes of gross errors, but these values obtained by using the proposed method are almost stable, which means an effective reduction of the influence of the gross errors by the proposed method as compared with the existing methods. It is also found that the larger the numbers and magnitudes of gross errors, the more obvious such a reduction. Furthermore, the experiment results with two sets of real-life data are consistent with the results of simulation experiments. Numéro de notice : A2017-543 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE/POSITIONNEMENT Nature : Article DOI : 10.1080/00396265.2016.1150088 En ligne : https://doi.org/10.1080/00396265.2016.1150088 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86598
in Survey review > vol 49 n° 354 (September 2017) . - pp 176 - 185[article]vol III-1 - July 2016 - [actes] XXIII ISPRS Congress, Commission I, 12–19 July 2016, Prague, Czech Republic (Bulletin de ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences) / Lena Halounova
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[n° ou bulletin]
est un bulletin de ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences / International society for photogrammetry and remote sensing (1980 -) (2012 - )
Titre : vol III-1 - July 2016 - [actes] XXIII ISPRS Congress, Commission I, 12–19 July 2016, Prague, Czech Republic Type de document : Périodique Auteurs : Lena Halounova, Éditeur scientifique ; V. Safar, Éditeur scientifique ; Charles K. Toth, Éditeur scientifique ; Jakub Karas, Éditeur scientifique ; Huadong Guo, Éditeur scientifique ; Norbert Haala, Éditeur scientifique ; A. Habib, Éditeur scientifique ; Peter Reinartz, Éditeur scientifique ; X. Tang, Éditeur scientifique ; J. Li, Éditeur scientifique ; Costas Armenakis, Éditeur scientifique ; Görres Grenzdorffer, Éditeur scientifique ; P. Le Roux, Éditeur scientifique ; Stratos Stylianidis, Éditeur scientifique ; Reinhard Blasi, Éditeur scientifique ; M. Menard, Éditeur scientifique ; H. Dufourmount, Éditeur scientifique ; Z. Li, Éditeur scientifique Congrès : ISPRS 2016, 23th international congress (12 - 19 juillet 2016; Prague, République tchèque), Auteur Année de publication : 2016 Langues : Français (fre) Numéro de notice : sans Affiliation des auteurs : non IGN Nature : Numéro de périodique En ligne : http://www.isprs-ann-photogramm-remote-sens-spatial-inf-sci.net/III-1/index.html Format de la ressource électronique : URL sommaire Permalink : https://documentation.ensg.eu/index.php?lvl=bulletin_display&id=27483 [n° ou bulletin] Contient
- Hybrid online mobile laser scanner calibration through image alignment by mutual information / Mourad Miled in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol III-1 (July 2016)
- Accuracy Validation of Large-scale Block Adjustment without Control of ZY3 Images over China / Yang Bo in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol III-1 (July 2016)
- Refined satellite image orientation in the free open-source photogrammetric tools Apero/MicMac / Ewelina Rupnik in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol III-1 (July 2016)
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Quality evaluation of the weekly vertical loading effects induced from continental water storage models / Z. Li (2016)
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Titre : Quality evaluation of the weekly vertical loading effects induced from continental water storage models Type de document : Article/Communication Auteurs : Z. Li, Auteur ; Tonie M. van Dam, Auteur ; Xavier Collilieux , Auteur ; Zuheir Altamimi
, Auteur ; Paul Rebischung
, Auteur ; Samuel Nahmani
, Auteur
Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2016 Collection : International Association of Geodesy Symposia, ISSN 0939-9585 num. 143 Conférence : IAG 2013, Scientific assembly, IAG 150 Years Postdam Allemagne Proceedings Springer Importance : pp 45 - 54 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Amérique du nord
[Termes IGN] coordonnées GPS
[Termes IGN] eaux continentales
[Termes IGN] effet de charge
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] série temporelleRésumé : (auteur) To remove continental water storage (CWS) signals from the GPS data, CWS mass models are needed to obtain predicted surface displacements. We compared weekly GPS height time series with five CWS models: (1) the monthly and (2) three-hourly Global Land Data Assimilation System (GLDAS); (3) the monthly and (4) one-hourly Modern-Era Retrospective Analysis for Research and Applications (MERRA); (5) the six-hourly National Centers for Environmental Prediction-Department of Energy (NCEP-DOE) global reanalysis products (NCEP-R-2). We find that of the 344 selected global IGS stations, more than 77% of stations have their weighted root mean square (WRMS) reduced in the weekly GPS height by using both the GLDAS and MERRA CWS products to model the surface displacement, and the best improvement concentrate mainly in North America and Eurasia. We find that the one-hourly MERRA-Land dataset is the most appropriate product for modeling weekly vertical surface displacement caused by CWS variations. The three-hourly GLDAS data ranks the second, while the GLDAS and MERRA monthly products rank the third. The higher spatial resolution MERRA product improves the performance of the CWS model in reducing the scatter of the GPS height by about 2–6% compared with the GLDAS. Under the same spatial resolution, the higher temporal resolution could also improve the performance by almost the same magnitude. We also confirm that removing the ATML and NTOL effects from the weekly GPS height would remarkably improve the performance of CWS model in correcting the GPS height by at least 10%, especially for coastal and island stations. Since the GLDAS product has a much greater latency than the MERRA product, MERRA would be a better choice to model surface displacements from CWS. Finally, we find that the NCEP-R-2 data is not sufficiently precise to be used for this application. Further work is still required to determine the reason. Numéro de notice : C2013-011 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1007/1345_2015_174 Date de publication en ligne : 30/07/2015 En ligne : https://doi.org/10.1007/1345_2015_174 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91895 Getting at the truth: A civilian GPS position authentication system / Z. Li in GPS world, vol 24 n° 1 (January 2013)
[article]
Titre : Getting at the truth: A civilian GPS position authentication system Type de document : Article/Communication Auteurs : Z. Li, Auteur ; Demoz Gebre-Egziabher, Auteur Année de publication : 2013 Article en page(s) : pp 67 - 73 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] authentification
[Termes IGN] positionnement par GPS
[Termes IGN] précision du positionnementRésumé : (Editeur) [...] Which brings us to GPS. When a GPS receiver reports its position to a monitoring center using a radio signal of some kind, how do we know that the receiver or its associated communications unit is telling the truth? It’s not that difficult to generate false position reports and mislead the monitoring center into believing the receiver is located elsewhere — unless an authentication procedure is used. In this month’s column, we look at the development of a clever system that uses the concept of supplicant and authenticator to assess the truthfulness of position reports. Numéro de notice : A2013-026 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32164
in GPS world > vol 24 n° 1 (January 2013) . - pp 67 - 73[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 067-2013011 RAB Revue Centre de documentation En réserve L003 Disponible
[n° ou bulletin]
est un bulletin de Cartography and Geographic Information Science / Cartography and geographic information society (1999 -)
Titre : vol 39 n° 3 - July 2012 Type de document : Périodique Auteurs : Z. Li, Auteur ; Cartography and geographic information society, Auteur Année de publication : 2012 Importance : 46 p. Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie Numéro de notice : 032-201203 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Numéro de périodique En ligne : http://www.ingentaconnect.com/content/cagis/cagis/2012/00000039/00000003;jsessio [...] Format de la ressource électronique : URL sommaire Permalink : https://documentation.ensg.eu/index.php?lvl=bulletin_display&id=12940 [n° ou bulletin] Contient
- Positional accuracy improvement using empirical analytic functions / C. Lopez-Vasquez in Cartography and Geographic Information Science, vol 39 n° 3 (July 2012)
- A hybrid system of expanding 2D GIS into 3D space / L. Yu in Cartography and Geographic Information Science, vol 39 n° 3 (July 2012)
- "Yu laid out the lands": georeferencing the Chinese Yujitu (Map of the Tracks of Yu) of 1136 / A. Akin in Cartography and Geographic Information Science, vol 39 n° 3 (July 2012)
Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 032-2012031 RAB Revue Centre de documentation En réserve L003 Disponible vol 39 n° 2 - April 2012 - Theories of map design in the digital era (Bulletin de Cartography and Geographic Information Science) / Z. Li
PermalinkEvaluation of the RPC model as a replacement for the spaceborne InSAR phase equation / G. Zhang in Photogrammetric record, vol 26 n° 135 (September - November 2011)
PermalinkICESat GLAS data for urban environment monitoring / P. Gong in IEEE Transactions on geoscience and remote sensing, vol 49 n° 3 (March 2011)
PermalinkEvaluation of the RPC model for spaceborne SAR imagery / G. Zhang in Photogrammetric Engineering & Remote Sensing, PERS, vol 76 n° 6 (June 2010)
PermalinkSelective omission of road features based on mesh density for automatic map generalization / J. Chen in International journal of geographical information science IJGIS, vol 23 n° 7-8 (july 2009)
PermalinkFusion of multispectral and panchromatic images using a restoration-based method / Z. Li in IEEE Transactions on geoscience and remote sensing, vol 47 n° 5 (May 2009)
PermalinkPermalinkDetermination of optimum window size for SAR image co-registration with decomposition of auto-correlation / W. Zou in Photogrammetric record, vol 22 n° 119 (September - November 2007)
PermalinkMulti-level topological relations between spatial regions based upon topological invariants / Min Deng in Geoinformatica, vol 11 n° 2 (June - August 2007)
PermalinkEffects of the intervals of tie points used in co-registration on the accuracy of digital elevation models generated by INSAR / W. Zou in Photogrammetric record, vol 21 n° 115 (September - November 2006)
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