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A simplified analytical model for a-priori Lidar pointpositioning error estimation and a review of Lidar error source / Mihaela Triglav Cekada in Photogrammetric Engineering & Remote Sensing, PERS, vol 75 n° 12 (December 2009)
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Titre : A simplified analytical model for a-priori Lidar pointpositioning error estimation and a review of Lidar error source Type de document : Article/Communication Auteurs : Mihaela Triglav Cekada, Auteur ; F. Crosilla, Auteur ; Mojca Kosmatin-Fras, Auteur Année de publication : 2009 Article en page(s) : pp 1425 - 1439 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] erreur de positionnement
[Termes IGN] erreur systématique
[Termes IGN] modèle d'erreur
[Termes IGN] qualité des données
[Termes IGN] source d'erreurRésumé : (Auteur) Although various rigorous lidar error models already exist and examples of a-posteriori studies of lidar data accuracies verified with field-work can be found in the literature, a simple measure to define a-priori error sizes is not available. In this paper, the lidar error contributions are described in detail: the basic systematic error sources, the flight-mission-related error sources, and the target-characteristic-related error sources. A review of the different error-source sizes is drawn from the literature in order to define the boundary conditions for each error size. Schenk’s geolocation equation is used as a basis for deriving a simplified error model. This model enables a quick calculation and gives a-priori plausible values for the average and maximum error size, independent of the scan and heading angles as well as being independent of any specific lidar system’s characteristics. Additionally, some notes are provided for assistance when ordering lidar data, to enable easier a-posteriori quality control. Copyright ASPRS Numéro de notice : A2009-501 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.75.12.1425 En ligne : https://doi.org/10.14358/PERS.75.12.1425 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30130
in Photogrammetric Engineering & Remote Sensing, PERS > vol 75 n° 12 (December 2009) . - pp 1425 - 1439[article]
[article]
Titre : Testing software receivers Type de document : Article/Communication Auteurs : A. Mitelman, Auteur ; J. Almqvist, Auteur ; R. Hakanson, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 28 - 34 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] instrument de géodésie
[Termes IGN] logiciel de post-traitement GPS
[Termes IGN] récepteur GPS
[Termes IGN] traitement de données GNSS
[Termes IGN] validité des donnéesRésumé : (Auteur) To meet the challenges inherent in producing a low-cost, highly CPU-efficient software receiver, the multiple offset post-processing method leverages the unique features of software GNSS to greatly improve the coverage and statistical validity of receiver testing compared to traditional, hardware-based testing setups, in some cases by an order of magnitude or more. Copyright Questex Media Group Numéro de notice : A2009-479 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30108
in GPS world > vol 20 n° 12 (December 2009) . - pp 28 - 34[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 067-09121 SL Revue Centre de documentation Revues en salle Disponible Using gravity and topography-implied anomalies to assess data requirements for precise geoid computation / Christopher Jekeli in Journal of geodesy, vol 83 n° 12 (December 2009)
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Titre : Using gravity and topography-implied anomalies to assess data requirements for precise geoid computation Type de document : Article/Communication Auteurs : Christopher Jekeli, Auteur ; H. Yang, Auteur ; J.H. Kwong, Auteur Année de publication : 2009 Article en page(s) : pp 1193 - 1202 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] anomalie de pesanteur
[Termes IGN] cohérence des données
[Termes IGN] Corée du sud
[Termes IGN] corrélation
[Termes IGN] géoïde gravimétrique
[Termes IGN] géoïde local
[Termes IGN] intégrale de Stokes
[Termes IGN] levé gravimétrique
[Termes IGN] nivellement par GPS
[Termes IGN] pesanteur terrestre
[Termes IGN] topographie localeRésumé : (Auteur) Many regions around the world require improved gravimetric data bases to support very accurate geoid modeling for the modernization of height systems using GPS. We present a simple yet effective method to assess gravity data requirements, particularly the necessary resolution, for a desired precision in geoid computation. The approach is based on simulating high-resolution gravimetry using a topography-correlated model that is adjusted to be consistent with an existing network of gravity data. Analysis of these adjusted, simulated data through Stokes’s integral indicates where existing gravity data must be supplemented by new surveys in order to achieve an acceptable level of omission error in the geoid undulation. The simulated model can equally be used to analyze commission error, as well as model error and data inconsistencies to a limited extent. The proposed method is applied to South Korea and shows clearly where existing gravity data are too scarce for precise geoid computation. Copyright Springer Numéro de notice : A2009-478 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-009-0337-y Date de publication en ligne : 20/08/2009 En ligne : https://doi.org/10.1007/s00190-009-0337-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30107
in Journal of geodesy > vol 83 n° 12 (December 2009) . - pp 1193 - 1202[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09111 SL Revue Centre de documentation Revues en salle Disponible Web data retrieval: solving spatial range queries using k-nearest neighbor searches / W. Bae in Geoinformatica, vol 13 n° 4 (December 2009)
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Titre : Web data retrieval: solving spatial range queries using k-nearest neighbor searches Type de document : Article/Communication Auteurs : W. Bae, Auteur ; S.H. Kim, Auteur ; S. Alkobaisi, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 483 - 514 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données
[Termes IGN] classification barycentrique
[Termes IGN] géomatique web
[Termes IGN] interface web
[Termes IGN] recherche d'information géographique
[Termes IGN] requête spatiale
[Termes IGN] système d'information géographiqueRésumé : (Auteur) As Geographic Information Systems (GIS) technologies have evolved, more and more GIS applications and geospatial data are available on the web. Spatial objects in a given query range can be retrieved using spatial range query - one of the most widely used query types in GIS and spatial databases. However, it can be challenging to retrieve these data from various web applications where access to the data is only possible through restrictive web interfaces that support certain types of queries. A typical scenario is the existence of numerous business web sites that provide their branch locations through a limited “nearest location” web interface. For example, a chain restaurant’s web site such as McDonalds can be queried to find some of the closest locations of its branches to the user’s home address. However, even though the site has the location data of all restaurants in, for example, the state of California, it is difficult to retrieve the entire data set efficiently due to its restrictive web interface. Considering that k-Nearest Neighbor (k-NN) search is one of the most popular web interfaces in accessing spatial data on the web, this paper investigates the problem of retrieving geospatial data from the web for a given spatial range query using only k-NN searches. Based on the classification of k-NN interfaces on the web, we propose a set of range query algorithms to completely cover the rectangular shape of the query range (completeness) while minimizing the number of k-NN searches as possible (efficiency). We evaluated the efficiency of the proposed algorithms through statistical analysis and empirical experiments using both synthetic and real data sets. Copyright Springer Numéro de notice : A2009-336 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-008-0055-2 En ligne : https://doi.org/10.1007/s10707-008-0055-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29966
in Geoinformatica > vol 13 n° 4 (December 2009) . - pp 483 - 514[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-09041 RAB Revue Centre de documentation En réserve L003 Disponible Coherent integration time : the longer, the better / T. Pany in Inside GNSS, vol 4 n° 6 (November - December 2009)
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Titre : Coherent integration time : the longer, the better Type de document : Article/Communication Auteurs : T. Pany, Auteur ; Bernhard Riedl, Auteur ; J. Winkel, Auteur Année de publication : 2009 Article en page(s) : 10 p. ; pp 52 - 61 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] centrale inertielle
[Termes IGN] filtre de Kalman
[Termes IGN] géonavigateur
[Termes IGN] GPS assisté pour la navigation (technologies)
[Termes IGN] intégration de données
[Termes IGN] magnétomètre
[Termes IGN] navigation à l'estime
[Termes IGN] positionnement en intérieur
[Termes IGN] positionnement par WiFi
[Termes IGN] prototype
[Termes IGN] récepteur GNSS
[Termes IGN] récepteur GPS
[Termes IGN] traitement du signal
[Termes IGN] WiFiRésumé : (Auteur) A common assumption in GNSS receiver design is that the coherent integration time should be less than a few dozens of milliseconds. This makes perfect sense for today’s commercial receivers due to data bit transitions, oscillator jitter, and user dynamics. However, a coherent integration time of several seconds would mitigate three important indoor positioning problems: multipath, cross-correlation false locks, and the squaring loss. Extending the integration time has a price, typically requiring an assistance data link providing data bits (or the use of pilot signals), a stable oscillator, and a sophisticated GNSS/INS integration to compensate for non-linear user motion. This column describes how those issues have been solved and the resulting benefits as demonstrated by a recently built prototype with a sensitivity of around 1.5 dBHz , more than 10 decibels beyond the current state of the art. Copyright Gibbons Media & Research LLC Numéro de notice : A2009-670 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33552
in Inside GNSS > vol 4 n° 6 (November - December 2009) . - 10 p. ; pp 52 - 61[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 159-09061 SL Revue Centre de documentation Revues en salle Disponible Documents numériques
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Coherent integration time ... - pdf éditeurAdobe Acrobat PDFExpire, QGIS, ARCGIS, POSTGIS : le quatuor géomatique de l'Aguda / Anonyme in Géomatique expert, n° 71 (octobre - novembre 2009)
PermalinkGeneration and application of rules for quality dependent facade reconstruction / S. Becker in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 6 (November - December 2009)
PermalinkL'information géographique à l'épreuve de l'innovation / Françoise de Blomac in SIG la lettre, n° 111 (novembre 2009)
PermalinkIntroducing scale parameters for adjusting area objects in GIS based on least squares and variance component estimation / X. Tong in International journal of geographical information science IJGIS, vol 23 n°11-12 (november 2009)
PermalinkPermalinkQuality assessment of linear data / S. Seo in International journal of geographical information science IJGIS, vol 23 n°11-12 (november 2009)
PermalinkPermalinkSensivity analysis of a decision tree classification to input data errors using a general Monte Carlo error sensitivity model / Zhi Huang in International journal of geographical information science IJGIS, vol 23 n°11-12 (november 2009)
Permalinkvol 30 n° 20 - October 2009 - Accuracy 2008, [actes], spatial accuracy in remote sensing, Shangai, 25 - 27 June 2008 (Bulletin de International Journal of Remote Sensing IJRS) / Jingxiong Zhang
PermalinkMultihulls: Spatial representation and processing with variable shape fidelity, applied to gazetteers / J.T. Hastings in Transactions in GIS, vol 13 n°5-6 (October/december 2009)
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