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Zeitschrift für Vermessungswesen ZFV (Bulletin de ZFV Zeitschrift für Vermessungswesen)
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Titre : Zeitschrift für Vermessungswesen ZFV Type de document : Périodique Editeur : Hannover : Deutscher Verein für Vermessungswesen DVW Année de publication : 2001 Langues : Allemand (ger) Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie Numéro de notice : 199-0101 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Numéro de périodique Permalink : https://documentation.ensg.eu/index.php?lvl=bulletin_display&id=5648 [n° ou bulletin]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 199-01011 RSREV Revue Centre de documentation En réserve L-101 Disponible Analysis of refraction influences in geodesy using image processing and turbulence models / Philipp Flach (2001)
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Titre : Analysis of refraction influences in geodesy using image processing and turbulence models Type de document : Thèse/HDR Auteurs : Philipp Flach, Auteur Editeur : Zurich : Schweizerischen Geodatischen Kommission / Commission Géodésique Suisse Année de publication : 2001 Collection : Geodätisch-Geophysikalische Arbeiten in der Schweiz, ISSN 0257-1722 num. 63 Importance : 175 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-908440-05-5 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] analyse spectrale
[Termes IGN] détecteur à transfert de charge
[Termes IGN] filtre de Wiener
[Termes IGN] instrument de géodésie
[Termes IGN] instrumentation Leica
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle atmosphérique
[Termes IGN] réfraction atmosphérique
[Termes IGN] spectre électromagnétique
[Termes IGN] traitement d'image
[Termes IGN] turbulence
[Termes IGN] variance
[Termes IGN] vidéothéodoliteIndex. décimale : 30.03 Instruments de géodésie Résumé : (Auteur) The propagation path of light in the atmosphere is influenced by inhomogeneities of the refractive index. These refraction effects deteriorate the accuracy of the direction and distance measurements in geodetic applications. As illustrated by two examples in this report, the refraction effects cannot be accurately corrected up to now and, therefore, solutions must be provided which can be implemented into geodetic instruments. The presented approach is based on the determination of the temperature gradient being the decisive influential parameter for angular refraction effects.
In the atmosphere, temperature gradients are related to turbulent thermal exchange processes such as the turbulent sensible heat flux. In order to describe atmospheric turbulence, the applied statistical approach uses the method of spectral analysis which states that the atmospheric turbulent velocity field can be thought to consist of many eddies of different densities. This energy spectrum of turbulence can be modelled using the structure constant of refractive index CJ and the inner scale 10 of turbulence. If these two structure parameters are measured, the temperature gradient is derived from dimensionless profile functions using the so-called Monin-Obukhov similarity description. Hereby, the fact should be kept in mind, that the Monin-Obukhov similarity description and the energy spectrum of turbulence are only valid for vertical temperature gradient profiles in the atmospheric boundary layer.
This research work investigates the determination of the required structure parameter Cn and lo by means of image sensors which can be built into geodetic instruments. To derive the structure parameters CJ and 10 from the acquired image data, the application of appropriate image processing techniques is examined. The evaluation concept is based on angle-of-arrival fluctuations and intensity fluctuations. Angle-of-arrival fluctuations are perceived as high-frequency motions of image patterns grabbed by the sensor, and intensity fluctuations are related to the temporal variation of the gray values of the pixels. As presented in this report, these two effects of optical turbulence can be used to determine the structure parameter Cn and lo. For this purpose, image processing techniques must parameterize both angle-of-arrival fluctuations and intensity fluctuations. Within this research work, the angle-of-arrival fluctuations are modelled by the variance óx characterizing the shifting of image patterns which are located using edge detection algorithms. The intensity fluctuations are modelled by the variance óx characterizing the temporal intensity spectrum of the incoming light beam. In the scope of this research work, the variance óx is provided using digital filter techniques such as the Wiener filter or least-squares template matching.
In order to validate this concept, the video theodolite Leica TM3000V and a digital line scan camera Basler L120 are used as two different imaging systems to acquire image data during various practical field experiments. These field experiments revealed a partial good agreement between the structure parameter CJ and lo obtained by the image sensors and the ones obtained by a reference system (scintillometer). Basically, the method presented here is appropriate to reduce the refraction influence. A decisive advantage of this method is based on the fact that additional sensors are not necessary (except for the image sensors which are built into the instrument). However, as the exemplary comparison of temperature gradients shows at the end of the report, further research work in the scope of the atmospheric boundary layer is still necessary.Numéro de notice : 13062 Affiliation des auteurs : non IGN Autre URL associée : http://dx.doi.org/10.3929/ethz-a-004045114 Thématique : POSITIONNEMENT Nature : Thèse étrangère DOI : 10.3929/ethz-a-004045114 En ligne : https://www.sgc.ethz.ch/sgc-volumes/sgk-63.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54863 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13062-01 30.03 Livre Centre de documentation En réserve M-103 Disponible 13062-02 30.03 Livre Centre de documentation En réserve M-103 Disponible Development of a dispersometer for the implementation into geodetic high-accuracy direction measurement systems / Burkhard Böckem (2001)
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Titre : Development of a dispersometer for the implementation into geodetic high-accuracy direction measurement systems Type de document : Thèse/HDR Auteurs : Burkhard Böckem, Auteur Editeur : Zurich : Institut für Geodäsie und Photogrammetrie IGP - ETH Année de publication : 2001 Collection : IGP Mitteilungen, ISSN 0252-9335 num. 73 Importance : 140 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-906467-33-7 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] effet atmosphérique
[Termes IGN] émetteur
[Termes IGN] impulsion laser
[Termes IGN] mesurage électronique d'angles
[Termes IGN] mesurage électronique de distances
[Termes IGN] propagation du signal
[Termes IGN] rayonnement électromagnétique
[Termes IGN] récepteur bifréquence
[Termes IGN] réfraction atmosphérique
[Termes IGN] téléscopeIndex. décimale : 30.03 Instruments de géodésie Résumé : (Auteur) In the course of the progressive developments of sophisticated geodetic systems which offer a very high accuracy potential strategies for correcting atmosphere-related effects will become increasingly important. These atmosphere-related effects arise in a large span of time scales: systematic deviations caused by a quasi-stationary refractive index gradient environment, generally referred to as refraction in geodetic context, slowly transfer to stochastic deviations resulting from optical turbulence. Refraction corrected optical direction and angle measurements are required in numerous high-accuracy measurement applications. These applications include surveying tasks in connection with civil engineering projects, the alignment of particle accelerator facilities, surveying tasks in context within assembling processes in industrial environments, e.g. aircraft industry, tasks wherein surveying instruments provide the spatial guidance of large machines, etc. A dispersometer, based on the dual-wavelength method by utilizing atmospheric dispersion, constitutes a metrological solution to atmosphere-related effects. Another decisive advantage of a dispersometer is that the envisaged correction of atmosphere-related effects works integrally and is available in real time. The aim of this thesis was to develop this dispersometer to overcome atmospherically induced limitations in very high-accuracy direction and angle measurements. The dispersometer consists of two modules: the dual-wavelength transmitter and the detection system being composed of the dispersion telescope and a position sensitive detector. By applying the dual-wavelength method, the major .challenges in instrumental realization are the generation of coaxial single-mode emission at two spectrally optimized wavelengths and the achievement of optical position sensing accuracy in the order of a few nanometers. The development of the dispersometer is principally made possible by focussing on three key technologies: dual-wavelength generation by frequency conversion, optical fiber technology, and gap- technology. Within this work detailed studies of these three key technologies are performed. In this work it is demonstrated that a dual-wavelength laser by frequency conversion is clearly suited for the implementation in the dual-wavelength transmitter. Furthermore, a novel technique for achieving coaxial single-mode propagation at two spectrally wide-separated wavelengths by one single-mode fiber is established within this thesis. Due to the application of optical fiber technology it is now possible to couple both beams into one optical channel of a modem geodetic total station. In order to achieve optical position sensing with the accuracy of a few nanometers by using a short-focal-length receiving telescope, gap-technology by utilizing special segmented position sensitive detectors is applied. This thesis contains a complete treatment addressed to this technology. Within the course of dispersometer performance tests, difference position sensing accuracy of ó = 7.3 nm was achieved. Additionally, the existence of the position sensitive detector inherent dispersion was demonstrated. In combination with the dispersion of the receiving optics, the position sensitive detector inherent dispersion has to be considered for the measurement of the atmospheric dispersion induced displacement between both beams of different wavelengths. As a solution a self-calibration procedure which corrects the dispersion of the complete detection system is described. This self-calibration procedure which utilizes the impact of optical turbulence possesses the decisive advantages that it obviates the need of additional measurements and the dispersion correction can be computed and applied in real time. A substantial part of this thesis is devoted to dispersometer measurements. Two basic atmospheric conditions which are typical for industrial measurement tasks indoors were simulated. Additionally, a detailed study of the influence of the aperture diameter on the dispersometer measurements was performed. The optimal aperture diameter for the present instrumental layout and for the prevailing ambient conditions was 30 mm. For theodolite-like and smaller apertures it is confirmed that the accuracy of the refraction angle improves with the square root of the integration time. Due to dispersometer performance by using theodolite-like and possibly smaller apertures in combination with the self-calibration procedure, the implementation of a standard theodolite-telescope is proposed. In a moderately turbulent atmosphere the accuracy of the refraction angle for single- face telescope observation was found to be 0.2 µrad (0.01 mgon) after an integration time of 12 sand a sight length of 17 m. Summarizing the theoretical investigations, the key technologies involved in the instrumental development, and the experimental results, presented in this dissertation, it can be concluded that the realized dispersometer in combination with a theodolite is capable of the refraction corrected angular measurements, the influences of optical turbulence notwithstanding. The application of optical fiber technology and the envisaged implementation of a standard theodolite-telescope confirm the presumption that the realized dispersometer can be implemented into modem geodetic total stations. Improvements with respect to field-operativeness are expected by an industrial realization of the dispersometer and by implementing the dispersometer into modem geodetic total stations. The integration of blue laser diodes, when meeting the standards of nowadays infrared laser diodes, would significantly enhance efficiency and reduce overall costs. Due to the technologies presented within this thesis such an integration is clearly feasible. Numéro de notice : 14740 Affiliation des auteurs : non IGN Autre URL associée : http://dx.doi.org/10.3929/ethz-a-004176211 Thématique : POSITIONNEMENT Nature : Thèse étrangère DOI : 10.3929/ethz-a-004176211 En ligne : http://e-collection.library.ethz.ch/eserv/eth:24109/eth-24109-02.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62684 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 14740-01 30.03 Livre Centre de documentation En réserve M-103 Disponible
Titre : Geodesy Type de document : Guide/Manuel Auteurs : Wolfgang Torge, Auteur Mention d'édition : 3rd completely revised and extended edition Editeur : Berlin, New York : Walter de Gruyter Année de publication : 2001 Importance : 416 p. Format : 17 x 24 cm ISBN/ISSN/EAN : 978-3-11-017072-6 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] astronomie
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] ellipsoïde de référence
[Termes IGN] force de gravitation
[Termes IGN] géodésie tridimensionnelle
[Termes IGN] géodynamique
[Termes IGN] géoïde
[Termes IGN] gravimétrie
[Termes IGN] interférométrie à très grande base
[Termes IGN] mesurage de distances
[Termes IGN] nivellement
[Termes IGN] positionnement par géodésie spatiale
[Termes IGN] réseau géodésique
[Termes IGN] réseau gravimétrique
[Termes IGN] système de référence céleste
[Termes IGN] système de référence géodésique
[Termes IGN] tectoniqueIndex. décimale : 30.00 Géodésie - généralités Résumé : (Editeur) This book covers the entire field of geodesy and is intended to serve as an introductory textbook for graduate students as well as a reference for scientists and engineers in the fields of geodesy, geophysics, surveying engineering, and geomatics. It provides a systematic overview of fundamental theories, geodetic reference systems, and spatial and terrestrial measurement methods, together with the respective modeling techniques. The third edition has been completely revised in order to adequately reflect the tremendous changes which have occured in geodesy in the last twenty years, where space techniques are now the predominante tool for positioning and gravity field determination. Establishment of geodetic control networks has followed these developments, with far-reaching consequences for applied geodesy. High data rates and improved accuracy have increased geodetic contributions to geodynamics research. The present state of geodesy is illustrated by selected examples of instruments and results of geodetic data processing. An extensive reference list supports further studies. Note de contenu : 1) Introduction
2) Reference systems
3) The gravity field of the earth
4) The geodetic earth model
5) Methods of measurement
6) Methods of evaluation
7) Geodetic and gravimetric networks
8) Structure and dynamics of the earthNuméro de notice : 13258 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Manuel de cours DOI : 10.1515/9783110879957.fm En ligne : https://doi.org/10.1515/9783110879957.fm Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54942 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13258-01 30.00 Livre Centre de documentation Géodésie Disponible 13258-02 DEP-ELG Livre Marne-la-Vallée Dépôt en unité Exclu du prêt Integrierte Modelle zur physikalischen Interpretation geodätischer Deformationsuntersuchungen / I. Milev (2001)
Titre : Integrierte Modelle zur physikalischen Interpretation geodätischer Deformationsuntersuchungen Titre original : [Modèles intégrés pour l'interprétation physique des études géodésiques de déformation] Type de document : Thèse/HDR Auteurs : I. Milev, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2001 Collection : DGK - C Sous-collection : Dissertationen num. 540 Importance : 105 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 3-7696-9579-6 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] filtre de Kalman
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle de déformation tectonique
[Termes IGN] transformation de Fourier
[Termes IGN] transformation de LaplaceIndex. décimale : 30.00 Géodésie - généralités Résumé : (Auteur) The presented integrated model for interpretation of measured displacements includes geodetic and mechanic relationships. This general relationship between the variation principle of mechanics and the general case of the least square adjustment will be delivered, and the geodetic calculation methods applied for use of variation objectives. This covers the Lagrange function with multipliers and presents an extended model for the potential. The complex deformation model based on the extended dynamical Hamilton's principle will be established and recommended as integrated solution. Numéro de notice : 13064 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54864 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13064-01 30.00 Livre Centre de documentation Géodésie Disponible PermalinkPermalinkvol 35 n° 4 - December 2000 (Bulletin de Artificial satellites. Planetary geodesy) / Polish academy sciences
Permalinkvol 54 n° 4 - December 2000 (Bulletin de Geomatica) / Canadian institute of geomatics = Association canadienne des sciences géomatiques (Canada)
Permalinkvol 125 n° 12 - Dezember 2000 (Bulletin de ZFV Zeitschrift für Vermessungswesen)
Permalinkvol 74 n°7-8 - November 2000 (Bulletin de Journal of geodesy) / International association of geodesy
PermalinkSurvey review (Bulletin de Survey review)
Permalinkvol 55 n° 9 - 01/10/2000 - Proceedings of the 2nd international workshop on "satellite navigation in CEI area", [actes], Olsztyn, 3 - 5 July 2000 (Bulletin de Reports on geodesy) / J. Sledzinski
Permalinkvol 35 n° 3 - September 2000 (Bulletin de Artificial satellites. Planetary geodesy) / Polish academy sciences
Permalinkvol 54 n° 3 - September 2000 (Bulletin de Geomatica) / Canadian institute of geomatics = Association canadienne des sciences géomatiques (Canada)
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