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The Forward Propagation of Integrated System Component Errors within Airborne Lidar Data / T. Goulden in Photogrammetric Engineering & Remote Sensing, PERS, vol 76 n° 5 (May 2010)
[article]
Titre : The Forward Propagation of Integrated System Component Errors within Airborne Lidar Data Type de document : Article/Communication Auteurs : T. Goulden, Auteur ; Christopher Hopkinson, Auteur Année de publication : 2010 Article en page(s) : pp 589 - 601 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] erreur en position
[Termes IGN] géoréférencement direct
[Termes IGN] GPS-INS
[Termes IGN] propagation d'erreur
[Termes IGN] varianceRésumé : (Auteur) Error estimates of lidar observations are obtained by applying the General Law of Propagation of Variances (GLOPOV) to the direct georeferencing equation. Within the formulation of variance propagation, the most important consideration is the values used to describe the error of the hardware component observations including the global positioning system, inertial measurement unit, laser ranger, and laser scanner (angular encoder noise and beam divergence). Data tested yielded in general, pessimistic predictions as 85 percent of residuals were within the predicted error level. Simulated errors for varying scan angles and altitudes produced horizontal errors largely influenced by IMU subsystem error as well as angular encoder noise and beam divergence. GPS subsystem errors contribute the largest proportion of vertical error only at shallow scan angles and low altitudes. The transformation of the domination of GPS related error sources to total vertical error occurs at scan angles of 23°, 13°, and 8° at flying heights of 1,200 m, 2,000 m, and 3,000 m AGL, respectively. Copyright ASPRS Numéro de notice : A2010-162 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.76.5.589 En ligne : https://doi.org/10.14358/PERS.76.5.589 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30357
in Photogrammetric Engineering & Remote Sensing, PERS > vol 76 n° 5 (May 2010) . - pp 589 - 601[article]Accuracy 2010 : Proceedings of the Ninth international symposium on spatial accuracy assessment in natural resources and environmental sciences, Leicester, UK, 20 - 23 juillet 2010 / Nicholas J. Tate (2010)
Titre : Accuracy 2010 : Proceedings of the Ninth international symposium on spatial accuracy assessment in natural resources and environmental sciences, Leicester, UK, 20 - 23 juillet 2010 Type de document : Actes de congrès Auteurs : Nicholas J. Tate, Éditeur scientifique ; Peter F. Fisher, Éditeur scientifique Editeur : Leicester [Royaume-Uni] : University of Leicester Année de publication : 2010 Autre Editeur : International Spatial Accuracy Research Association ISARA Conférence : Accuracy 2010, 9th international symposium on spatial accuracy assessment in natural resources and environmental sciences 20/07/2010 23/07/2010 Leicester Royaume-Uni OA Proceedings Importance : 436 p. Format : 21 x 30 cm Langues : Anglais (eng) Descripteur : [Termes IGN] données localisées des bénévoles
[Termes IGN] géostatistique
[Termes IGN] géovisualisation
[Termes IGN] incertitude des données
[Termes IGN] incertitude géométrique
[Termes IGN] incertitude temporelle
[Termes IGN] précision des données
[Termes IGN] propagation d'erreur
[Termes IGN] sous ensemble flou
[Termes IGN] traitement de données localiséesIndex. décimale : CG2010 Actes de congrès en 2010 Note de contenu : 1 - Keynotes
2 - Remote sensing and image interpretation
3 - Fuzzy uncertainty 1
4 - Uncertainty in space and time
5 - Geostatistics 1
6 - ISPRS session
7 - Uncertainty propagation
8 - Land use and land cover
9 - DEM uncertainty 1
10 - Remote sensing
11 - Geoprocessing
12 - Model uncertainty and validation
13 - Vizualisation
14 - Sampling design
15 - Spatio-temporal uncertainty
16 - DEM uncertainty 2
17 - Geostatistics 2
18 - Fuzzy uncertainty 2
19 - DEM uncertainty 3
20 - Remote sensing classification
21 - Environmental quality
22 - Small area concerns
23 - Ecology and forestry
24 - VGI and web-based geoprocessing
25 - Geocoding and adress coding
26 - PostersNuméro de notice : 21370 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Actes DOI : sans En ligne : http://spatialaccuracy.org/spatial-accuracy-2010/ Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90097 ContientRéservation
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Code-barres Cote Support Localisation Section Disponibilité 21370-01 CG2010 Livre Centre de documentation Congrès Disponible Improving dilution of precision: a companion measure of systematic effects / D. Milbert in GPS world, vol 20 n° 11 (November 2009)
[article]
Titre : Improving dilution of precision: a companion measure of systematic effects Type de document : Article/Communication Auteurs : D. Milbert, Auteur Année de publication : 2009 Article en page(s) : pp 38 - 46 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] affaiblissement de la précision
[Termes IGN] erreur aléatoire
[Termes IGN] erreur de mesure
[Termes IGN] erreur de positionnement
[Termes IGN] erreur systématique
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] modèle d'erreur
[Termes IGN] positionnement par GNSS
[Termes IGN] propagation d'erreurRésumé : (Editeur) [...] If we lived in an ideal world, a receiver could make perfect measurements and model them exactly. Then, we would only need measurements to any four satellites to determine our position perfectly. Unfortunately, the receiver must deal with measurements and models that have some degree of error, which gets propagated into the position solution. Furthermore, the geometrical arrangement of the satellites observed by the receiver their elevation angles and azimuths can significantly affect the precision and accuracy of the receiver's solution, typically degrading them.
It is common to express the degradation or dilution by dilution of precision (DOP) factors. Multiplying the measurement and model uncertainty by an appropriate DOP value gives an estimate of the position error. These estimates are reasonable if the measurement and model errors are truly random. However, it turns out that this simple geometrical relationship breaks down if some model errors are systematic. If that systematic error is a constant bias and if it is common to all pseudoranges measured simultaneously, then the receiver can easily estimate it along with its clock offset, leaving the position solution unaffected. But if the errors are systematically different for the different simultaneous pseudoranges, as is typically the case when trying to correct for ionospheric and tropospheric effects, these errors propagate into the receiver solution in a way that is fundamentally different from the way that random errors propagate. This means that in addition to DOP, we need a companion measure of systematic effects. In this month's column, Dennis Milbert introduces just such a measure the error scale factor or ESF. ESF, combined with DOP, forms a hybrid error model that appears to more realistically portray the real-world GPS precisions and accuracies we actually experience. Copyright Questex Media GroupNuméro de notice : A2009-407 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30038
in GPS world > vol 20 n° 11 (November 2009) . - pp 38 - 46[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 067-09111 SL Revue Centre de documentation Revues en salle Disponible Efficient propagation of error covariance matrices of gravitational models: application to GRACE and GOCE / Georges Balmino in Journal of geodesy, vol 83 n° 10 (October 2009)
[article]
Titre : Efficient propagation of error covariance matrices of gravitational models: application to GRACE and GOCE Type de document : Article/Communication Auteurs : Georges Balmino, Auteur Année de publication : 2009 Article en page(s) : pp 989 - 995 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] données GOCE
[Termes IGN] données GRACE
[Termes IGN] harmonique sphérique
[Termes IGN] matrice de covariance
[Termes IGN] modèle de géopotentiel
[Termes IGN] propagation d'erreurRésumé : (Auteur) We have applied efficient methods for computing variances and covariances of functions of a global gravity field model expanded in spherical harmonics, using the full variance–covariance matrix of the coefficients. Examples are given with recent models derived from GRACE (up to degree and order 150), and with simulated GOCE derived solutions (up to degree and order 200). Copyright Springer Numéro de notice : A2009-432 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-009-0317-2 En ligne : https://doi.org/10.1007/s00190-009-0317-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30063
in Journal of geodesy > vol 83 n° 10 (October 2009) . - pp 989 - 995[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-09091 SL Revue Centre de documentation Revues en salle Disponible The effects of quality control on decreasing error propagation in the LandScan USA population distribution model: a case study of Philadelphia County / L. Patterson in Transactions in GIS, vol 13 n° 2 (April 2009)
[article]
Titre : The effects of quality control on decreasing error propagation in the LandScan USA population distribution model: a case study of Philadelphia County Type de document : Article/Communication Auteurs : L. Patterson, Auteur ; M. Urban, Auteur ; A. Myers, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 215 - 228 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] contrôle qualité
[Termes IGN] démographie
[Termes IGN] détection de changement
[Termes IGN] géostatistique
[Termes IGN] image à moyenne résolution
[Termes IGN] Philadelphie
[Termes IGN] propagation d'erreur
[Termes IGN] répartition géographiqueRésumé : (Auteur) LandScan USA is a 90 m population distribution model that is used for a variety of applications, including emergency management. Models should have a measure of accuracy; however, the accuracy of population distribution models is difficult to determine due to the inclusion of multiple input datasets and the lack of quantifiable, observable (validated) data to confirm model output. Validated data enables quantification of: (1) overall model accuracy and (2) changes in model output at different levels of quality control. This article examines the effect of quality control for two national school datasets incorporated as input in LandScan USA for Philadelphia County, Pennsylvania; which had a local, validated school dataset available. The effect of each stage of quality control efforts utilized throughout the LandScan USA process were assessed to determine what level of quality control was required to have a statistically significant change of the model's population distribution. The typical level of quality control for LandScan USA resulted in 36% of schools being moved to the correct location and 20% of missing student enrollments were found, compared to 87% and 98% respectively for the validated dataset. The costs of increasing quality control resulted in a six-fold increase in labor time; however, the additional quality control did not produce statistically significant improvements in the LandScan USA model. Thus, typical quality control efforts for schools in LandScan USA produced a population distribution similar to the validated level of quality control, and can be applied with confidence for policy, planning, and emergency situations. Copyright Blackwell Publishing Numéro de notice : A2009-542 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/j.1467-9671.2009.01148.x En ligne : https://doi.org/10.1111/j.1467-9671.2009.01148.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30171
in Transactions in GIS > vol 13 n° 2 (April 2009) . - pp 215 - 228[article]Accuracy assessment of digital elevation models based on approximation theory / P. Hu in Photogrammetric Engineering & Remote Sensing, PERS, vol 75 n° 1 (January 2009)PermalinkAdjustability and error propagation for true replacement sensor models / C. Puatanachokchai in ISPRS Journal of photogrammetry and remote sensing, vol 63 n° 3 (May - June 2008)PermalinkDétection automatique des points de fuite et calcul de leur incertitude à l'aide de la géométrie projective / Mahzad Kalantari (2008)PermalinkModelling landscape dynamics with Python / D. Karssenberg in International journal of geographical information science IJGIS, vol 21 n° 5 (may 2007)PermalinkOn the prediction error variance of the common spatial interpolation schemes / P.C. Kyriakidis in International journal of geographical information science IJGIS, vol 20 n° 8 (september 2006)PermalinkUncovering the statistical and spatial characteristics of fine toposcale DEM error / Juha Oksanen in International journal of geographical information science IJGIS, vol 20 n° 4 (april 2006)PermalinkThe accuracy of grid digital elevation models linearly constructed from scattered sample data / F. Aguilar in International journal of geographical information science IJGIS, vol 20 n° 2 (february 2006)PermalinkSensitivity analysis and uncertainty analysis for vector geographical applications / Olivier Bonin (2006)PermalinkEffect of the STRM global DEM on the determination of a high-resolution geoid model: A case study in Iran / R. Kiamehr in Journal of geodesy, vol 79 n° 9 (December 2005)PermalinkRéflexions sur les incertitudes et leurs propagations en analyse spatiale / R. Caloz in Revue internationale de géomatique, vol 15 n° 3 (septembre – novembre 2005)Permalink