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Digital terrain model quality assessment : insights on how to minimize and handle common artefacts / Olivier Bonin (2004)
contenu dans Proceedings of the ISSDQ'04, Volume 1. [3rd international symposium on spatial data quality] / Andrew U. Franck (2004)
Titre : Digital terrain model quality assessment : insights on how to minimize and handle common artefacts Type de document : Article/Communication Auteurs : Olivier Bonin , Auteur ; Frédéric Rousseaux, Auteur
Editeur : Vienne [Autriche] : Vienna University of Technology Année de publication : 2004 Collection : GeoInfo series num. 28a Conférence : ISSDQ 2004, 3rd International Symposium on Spatial Data Quality 15/04/2004 17/04/2004 Vienne Autriche Importance : pp 121 - 124 Langues : Anglais (eng) Descripteur : [Termes IGN] artefact
[Termes IGN] modèle numérique de terrain
[Termes IGN] qualité des donnéesNuméro de notice : C2004-035 Affiliation des auteurs : COGIT (1988-2011) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101031 GPS based determination of the integrated and spatially distributed water vapor in the troposphere / Marc Troller (2004)
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Titre : GPS based determination of the integrated and spatially distributed water vapor in the troposphere Type de document : Thèse/HDR Auteurs : Marc Troller, Auteur Editeur : Zurich : Schweizerischen Geodatischen Kommission / Commission Géodésique Suisse Année de publication : 2004 Collection : Geodätisch-Geophysikalische Arbeiten in der Schweiz, ISSN 0257-1722 num. 67 Importance : 172 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-908440-10-9 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] correction troposphérique
[Termes IGN] distribution spatiale
[Termes IGN] modèle atmosphérique
[Termes IGN] positionnement par GPS
[Termes IGN] propagation troposphérique
[Termes IGN] Suisse
[Termes IGN] teneur en vapeur d'eau
[Termes IGN] tomographie
[Termes IGN] traitement du signal
[Termes IGN] troposphère
[Termes IGN] vapeur d'eauIndex. décimale : 30.84 Applications de géodésie spatiale à l'atmosphère Résumé : (Auteur) Climate change and global warming have become a major challenge for the sustainable development of our Earth and its environment. Intensive research is carried out to understand atmospheric processes and their implications. In this content, water vapor plays a key role. It is an important component of the global energy balance and is involved in many chemical reactions. In microwave measurements, the tropospheric refractivity causes a delay in the arrival of the signal propagating through the atmosphere. This refraction effect is one of the limiting factors in accurate GPS positioning. The tropospheric path delay can be decomposed into a dry and wet part, where the latter part is coupled with the integrated precipitable water vapor above the GPS receiver.
On the one hand, the refraction effect has to be corrected for GPS measurements, on the other hand, it is a valuable signal to determine the spatial distribution of the water vapor. This study investigates both aspects. For the first part, two basic approaches are looked into: One method is based on meteorological measurements. Thereby, the integrated amount of water vapor and its temporal variation are the prime target. The other concept makes use of long-term GPS measurements. The arrival delay of the GPS signals are used, to estimate the integrated amount of water vapor. This result can then be the basis to determine its spatial distribution and temporal behavior. The investigation is based on a tomographic approach and forms the main content of part 2 of this work.
In part 1, an extension of the software package COMEDIE is developed and applied to determine tropospheric path delays. COMEDIE allows a four-dimensional modeling (in space and time) of the meteorological parameters air pressure, temperature and water vapor pressure using a collocation approach. Integrating the meteorological parameters, tropospheric path delays are obtained. Evaluations and comparisons in Switzerland show the performance of this method. An overall good agreement was achieved compared to GPS-estimated path delays. The accuracy depends on the season, and is in the range of 1-2 cm for the tropospheric path delay.
Continuous GPS measurements allow to estimate tropospheric path delays in the GPS processing. In a second approach of part 1, a method based on such GPS-estimated path delays is developed. It uses - like COMEDIE - a four-dimensional model and a collocation adjustment to estimate tropospheric path delays at desired locations. Evaluations are carried out in the area of Switzerland using the permanent GPS network AGNES. Long-term time series of cross-correlations are analyzed. An accuracy of 0.5 - 1.5 cm is obtained.
To resolve the GPS-estimated water vapor in the vertical, a tomographic approach is investigated in part 2 of this study. It is based on the assimilation of GPS double-difference observations. The wet refractivity field is determined applying a least-squares adjustment. To test the performance of the software, different weather conditions are simulated. Various stochastically constrained models are applied and discussed in terms of inversion stability. Results from real data gathered during a dedicated measurement campaign in the high density GPS network of the Big Island of Hawaii are analyzed. Compared to radiosondes, an accuracy of about 10 ppm (refractivity units) is achieved.
To compare the potential and limits of the investigated methods, independent data must be available. An extensive study is performed in the area of Switzerland to evaluate and compare all presented methods with each other. For the validation, data of the numerical weather model aLMo are used. Seven days of data in a high spatial distribution and on an hourly basis are investigated. The tropospheric path delays resulting from the various methods are compared and analyzed. An overall good agreement with the aLMo data was observed. To evaluate the spatial distribution of water vapor, 7680 refractivity profiles are determined with the tomographic method and compared with the numerical weather data. The analysis contains four tomographic approaches including different types of constraints. The results are statistically evaluated and compared. A correlation between the accuracy and the weather situation was found. Overall, an agreement of 5-7 ppm (refractivity units) was achieved compared to aLMo.
In conclusion, it can be stated that the determination of the integrated amount of water vapor in the troposphere was successfully performed. For the main geodetic application, the correction of GPS measurements, the estimation of path delays in the GPS processing is recommended, provided long-terrn GPS phase observations are available. For the determination of the spatial distribution and the temporal variation of the integrated amount of water vapor, modeling of the GPS-estimated path delays is a successful method. Moreover, the principal feasibility to resolve the vertical distribution of the water vapor applying the tomographic approach was demonstrated. However, further investigations concerning constraints or the introduction of additional information are required.Numéro de notice : 13264 Affiliation des auteurs : non IGN Autre URL associée : http://dx.doi.org/10.3929/ethz-a-004796376 Thématique : POSITIONNEMENT Nature : Thèse étrangère DOI : 10.3929/ethz-a-004796376 En ligne : https://www.sgc.ethz.ch/sgc-volumes/sgk-67.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54945 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13264-01 30.84 Livre Centre de documentation Géodésie Disponible 13264-02 30.84 Livre Centre de documentation Géodésie Disponible
Titre : GPS satellite surveying Type de document : Guide/Manuel Auteurs : Alfred Leick, Auteur Mention d'édition : 3 Editeur : New York, Londres, Hoboken (New Jersey), ... : John Wiley & Sons Année de publication : 2004 Importance : 436 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-0-471-05930-1 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] ambiguïté entière
[Termes IGN] compensation de coordonnées
[Termes IGN] compensation Lambda
[Termes IGN] compensation par moindres carrés
[Termes IGN] correction ionosphérique
[Termes IGN] correction troposphérique
[Termes IGN] Galileo
[Termes IGN] Global Orbitography Navigation Satellite System
[Termes IGN] Global Positioning System
[Termes IGN] mesurage de phase
[Termes IGN] mesurage de pseudo-distance
[Termes IGN] orbitographie
[Termes IGN] phase GPS
[Termes IGN] positionnement absolu
[Termes IGN] positionnement cinématique
[Termes IGN] positionnement différentiel
[Termes IGN] positionnement dynamique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement par GPS
[Termes IGN] positionnement statique
[Termes IGN] propagation ionosphérique
[Termes IGN] propagation troposphérique
[Termes IGN] signal GPS
[Termes IGN] surface de référence
[Termes IGN] système de positionnement par satellites
[Termes IGN] système de référence géodésique
[Termes IGN] traitement de données GNSSIndex. décimale : 30.61 Systèmes de Positionnement par Satellites du GNSS Résumé : (Editeur) This new edition is thoroughly updated to reflect extensive changes in Global Positioning Systems, and is the first GPS book to integrate data from Russian GLONASS and European GALILEO GPS systems into U.S GPS data and procedures. Note de contenu : Preface. Acknowledgements. Abbreviations.
Chapter 1. Introduction.
Chapter 2. Geodetic Reference Systems.
Chapter 3. Satellite Systems.
Chapter 4. LSQ Adjustments.
Chapter 5. Pseudorange and Career Phase Observiables.
Chapter 6. Troposphere and Ionosphere.
Chapter 7. Processing Pseudoranges and Career Phases.
Chapter 8. Network Adjustments.
Chapter 9. Two-Dimensional Geodetic Models.
Appendix A. General Background.
Appendix B. The Ellipsoïd.
Appendix C. Conformal Mapping. References. Spelling Dictionary.Numéro de notice : 12163 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Manuel de cours Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54566 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 12163-01 30.61 Livre Centre de documentation Géodésie Disponible 12163-04 30.61 Livre Centre de documentation Géodésie Disponible 12163-02 DEP-ELG Livre Marne-la-Vallée Dépôt en unité Exclu du prêt 12163-03 DEP-ELG Livre Marne-la-Vallée Dépôt en unité Exclu du prêt
Titre : Ground penetrating radar, 2nd edition Type de document : Monographie Auteurs : D.J. Daniels, Éditeur scientifique Mention d'édition : 2 Editeur : London : The Institution of Engineering and Technology IET Année de publication : 2004 Collection : IET Radar, Sonar, Navigation and Avionics Series num. 15 Importance : 726 p. Format : 16 x 24 cm + 1 cédérom ISBN/ISSN/EAN : 978-0-86341-360-5 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] antenne radar
[Termes IGN] archéométrie
[Termes IGN] déconvolution
[Termes IGN] écho radar
[Termes IGN] érosion
[Termes IGN] filtrage du bruit
[Termes IGN] génie civil
[Termes IGN] glace
[Termes IGN] glacier
[Termes IGN] mine antipersonnel
[Termes IGN] modèle numérique
[Termes IGN] neige
[Termes IGN] pédologie
[Termes IGN] pollution des sols
[Termes IGN] prospection minérale
[Termes IGN] radar à antenne synthétique
[Termes IGN] radar pénétrant GPR
[Termes IGN] radargrammétrie
[Termes IGN] rugosité du sol
[Termes IGN] télédétection en hyperfréquence
[Termes IGN] tomographie
[Termes IGN] traitement du signalIndex. décimale : 35.22 Télédétection en hyperfréquence - Traitement d'image radar Résumé : (Editeur) Ground penetrating radar has come to public attention in recent criminal investigations, but has been a developing and maturing remote sensing field for some time. In the light of recent expansion of the technique to a wide range of applications, the need for an up-to-date reference has become urgent. This fully revised and expanded edition of the best-selling Surface-Penetrating Radar (IEE, 1996) presents, for the non-specialist user or engineer, all the key elements of this technique, which span several disciplines including electromagnetics, geophysics and signal processing. The book will help users to assess the potential of the technique and currently available technology and to apply them effectively. Numéro de notice : 20106 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62915 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 20106-01 35.22 Livre Centre de documentation Télédétection Disponible Jamming protection of GPS receivers: part 1 receiver enhancements / S. Rounds in GPS world, vol 15 n° 1 (January 2004)
[article]
Titre : Jamming protection of GPS receivers: part 1 receiver enhancements Type de document : Article/Communication Auteurs : S. Rounds, Auteur Année de publication : 2004 Article en page(s) : pp 54 - 59 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] brouillage
[Termes IGN] centrale inertielle
[Termes IGN] récepteur GPS
[Termes IGN] signal GPSRésumé : (Editeur) During military operations, jamming of an adversary's radio and radar signals is a common tactic and, in fact, is now an integral part of electronic warfare. In an attempt to thwart such jamming threats, military planners are continually developing antijamming techniques. Such is the case with GPS. Although its spread-spectrum nature affords it some protection form interfering signals, the signal is so weak that it can be readily overpowered by even a low-power nearby jammer or by a strong jammer at distances of up to many hundrerds of kilometers. This month's column features the second installment of a two-part article on jamming protection for GPS receivers. In part 1, we look at enhancements to receiver design - primarily by integrating the GPS sensor with an inertial measuring unit. Copyright Questex Media Group Inc Numéro de notice : A2004-599 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27115
in GPS world > vol 15 n° 1 (January 2004) . - pp 54 - 59[article] Voir aussiRéservation
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