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Auteur Jorma Jokela |
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The European GeoMetre project: developing enhanced large-scale dimensional metrology for geodesy / Florian Pollinger in Applied geomatics, vol 15 n° inconnu (2023)
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Titre : The European GeoMetre project: developing enhanced large-scale dimensional metrology for geodesy Type de document : Article/Communication Auteurs : Florian Pollinger, Auteur ; Sergio Baselga, Auteur ; Clément Courde, Auteur ; Cornelia Eschelbach, Auteur ; Luis García-Asenjo, Auteur ; Pascual Garrigues, Auteur ; Joffray Guillory, Auteur ; Per Olof Hedekvist, Auteur ; Tuomas Helojärvi, Auteur ; Jorma Jokela, Auteur ; Ulla Kallio, Auteur ; Thomas Klügel, Auteur ; Paul Köchert, Auteur ; Michael Lösler, Auteur ; Raquel Luján, Auteur ; Tobias Meyer, Auteur ; Pavel Neyezhmakov, Auteur ; Damien Pesce, Auteur ; et al., Auteur Année de publication : 2023 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] grande échelle
[Termes IGN] métrologie tridimensionnelleRésumé : (auteur) We provide a survey on the joint European research project “GeoMetre”, which explores novel technologies and their inclusion to existing surveying strategies to improve the traceability of geodetic reference frames to the SI definition of the metre. This work includes the development of novel distance meters with a range of up to 5 km, the realisation of optical multilateration systems for large structure monitoring at an operation distance of 50 m and beyond, and a novel strategy for GNSS-based distance determination. Different methods for refractivity compensation, based on classical sensors, on dispersion, on spectroscopic thermometry, and on the speed of sound to reduce the meteorological uncertainties in precise distance measurements, are developed further and characterised. These systems are validated at and applied to the novel European standard baseline EURO5000 at the Pieniny Kippen Belt, Poland, which was completely refurbished and intensely studied in this project. We use our novel instruments for a reduced uncertainty of the scale in the surveillance networks solutions for local tie measurements at space-geodetic co-location stations. We also investigate novel approaches like close-range photogrammetry to reference point determination of space-geodetic telescopes. Finally, we also investigate the inclusion of the local gravity field to consider the deviations of the vertical in the data analysis and to reduce the uncertainty of coordinate transformations in this complex problem. Numéro de notice : A2023-089 Affiliation des auteurs : IGN+Ext (2020- ) Autre URL associée : vers HAL Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s12518-022-00487-3 Date de publication en ligne : 20/02/2023 En ligne : https://doi.org/10.1007/s12518-022-00487-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103089
in Applied geomatics > vol 15 n° inconnu (2023)[article]
Titre : Interference measurements of the Nummela standard baseline in 2005 and 2007 Type de document : Monographie Auteurs : Jorma Jokela, Auteur ; P. Häkli, Auteur Editeur : Helsinki : Finnish Geodetic Institute FGI Année de publication : 2010 Collection : Publications of the Finnish Geodetic Institute, ISSN 0085-6932 num. 144 Importance : 90 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-951-711-283-3 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] comparateur de Vaisala
[Termes IGN] Finlande
[Termes IGN] interférence
[Termes IGN] ligne de base
[Termes IGN] mesurage électronique de distancesRésumé : (Auteur) The Nummela Standard Baseline of the Finnish Geodetic Institute is a unique national and international measurement standard for length measurements in geodesy. The design of the 864-m baseline was originally, in 1933, fitted for the calibration of 24-m invar wires to determine a uniform scale for triangulation. Since 1947, the baseline has been regularly measured with the Vaisala interference comparator. As a continuation to the impressive time series, the performance and results of the latest interference measurements in 2005 and 2007 are presented in detail in this publication. Two consecutive measurements within a short time span were necessary, since only half of the baseline could be measured in 2005, due to unfavourable weather conditions. The new results again confirm the excellent stability and unique accuracy, 9xlO"8, of the baseline. The 6-pillar baseline now serves in the calibration, testing and validation of electronic distance measurement (EDM) instruments for precise surveying and mapping and in scale transfer measurements to other geodetic baselines, test fields and local geodynamical networks. The measurements are metrologically traceable to the definition of the metre through a quartz gauge system.
This publication provides a summary of the rare measurement method and is a detailed supplement to the previously published or internal instruction manuals. First, we present the quartz gauge systems, which determine the scale in the Vaisala interference comparator. After a description of the present comparison method for the quartz gauges, the computation of the scale for the latest interference measurements is presented. For the interference measurements, the comparator must be separately constructed for every baseline. We describe the preparations and installations for this, followed by the observation and computation procedures. The abundant illustrations clarify the many stages. For further utilization of the baseline, the projection measurements are an essential part of the entire measurement. They transfer the distances between the mirror surfaces in the comparator to the distances between the permanently fixed transferring bars on the observation pillars, and, finally, to the baseline lengths between the underground benchmarks. We present the estimation of the uncertainty of measurement as standard and expanded uncertainties, combining all of the sources of the uncertainty in the traceability chain.
The standard uncertainties of the new results range from ±0.02 mm to ±0.07 mm for the lengths of the baseline sections ranging from 24 m to 864 m. The result for the length of the entire baseline, 864 122.86 mm ±0.07 mm, differs +0.11 mm from the previous result in 1996 and +0.08 mm from the first result in 1947. The largest difference between the results in 2005 and 2007 is -0.08 mm. The state-of-the-art Nummela Standard Baseline remains a world-class measurement standard of geodetic length metrology.Note de contenu : 1 Introduction
2 Landmarks in the history of the Nummela Standard Baseline
2.1 First international recognitions
2.2 Change from invar wires to EDM instruments as transfer standards
2.3 Recent construction works
2.4 Importance in the 2010s
3 Traceability chain of geodetic length measurements
4 Quartz gauges in the determination of the scale
4.1 Review of quartz gauge systems at Tuorla Observatory
4.2 Comparisons at Tuorla Observatory
4.3 Determination of the length of quartz gauge no. VIII in BTM00
5 Preparing the baseline for interference measurements
5.1 Principle of the Vaisala interference comparator
5.2 Preparing the observation pillars for interference measurements
5.3 Precise levellings - start of the measurements
5.4 Aligning the mirrors
5.5 Setting the mirrors at correct positions in the baseline direction
5.6 Installing the transferring bars onto the observation pillars
5.7 Installations on the telescope pillar
5.8 Installations on pillars 0 and 1
6 Interference observations
6.1 Observation procedure
6.2 About weather conditions
6.3 Personnel
7 Determination of corrections
7.1 Compensator corrections
7.2 Refraction correction
7.3 Corrections due to mirrors
7.4 Geometric corrections
7.5 Projection corrections
8 Computation of baseline lengths
8.1 Computation of the actual length of the quartz gauge
8.2 Results from interference observations in 2005
8.3 Results from interference observations in 2007
8.4 Final lengths
9 Estimation of uncertainty of measurement
9.1 Combined uncertainty of the lengths between the underground markers
9.2 Some supplementary analysis of uncertainty of measurement
10 Summary and conclusionsNuméro de notice : 14650 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie En ligne : https://www.maanmittauslaitos.fi/sites/maanmittauslaitos.fi/files/fgi/FGI_Publ_1 [...] Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62678 Documents numériques
en open access
14650_fgi-publ-144_jokela.pdfAdobe Acrobat PDF
Titre : Kyviskes calibration baseline Type de document : Rapport Auteurs : Jorma Jokela, Auteur ; P. Petroskevicius, Auteur ; V. Tulevicius, Auteur Editeur : Helsinki : Finnish Geodetic Institute FGI Année de publication : 1999 Collection : Reports of the Finnish Geodetic Institute num. 99-3 Importance : 15 p. Format : 21 x 30 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Triangulation
[Termes IGN] base d'étalonnage
[Termes IGN] calibrageIndex. décimale : 30.32 Travaux de triangulation Numéro de notice : 54757 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=59694 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 54757-01 30.32 Livre Centre de documentation En réserve M-103 Disponible
Titre : Interference measurements of the Chang Yang standard baseline in 1994 Type de document : Monographie Auteurs : Jorma Jokela, Auteur Editeur : Helsinki : Finnish Geodetic Institute FGI Année de publication : 1996 Collection : Publications of the Finnish Geodetic Institute, ISSN 0085-6932 num. 121 Importance : 32 p. Format : 18 x 25 cm ISBN/ISSN/EAN : 978-951-711-191-1 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Triangulation
[Termes IGN] base d'étalonnage
[Termes IGN] Chine
[Termes IGN] correction
[Termes IGN] Fleuve bleu (Chine)
[Termes IGN] interférenceIndex. décimale : 30.32 Travaux de triangulation Numéro de notice : 64365 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=61330 Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 64365-01 30.32 Livre Centre de documentation En réserve M-103 Disponible 64365-02 30.32 Livre Centre de documentation En réserve M-103 Disponible
Titre : The 1993 adjustement of the Finnish first-order terrestrial triangulation Type de document : Monographie Auteurs : Jorma Jokela, Auteur Editeur : Helsinki : Finnish Geodetic Institute FGI Année de publication : 1994 Collection : Publications of the Finnish Geodetic Institute, ISSN 0085-6932 num. 119 Importance : 137 p. Format : 18 x 25 cm ISBN/ISSN/EAN : 978-951-711-173-7 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Triangulation
[Termes IGN] compensation de coordonnées
[Termes IGN] Finlande
[Termes IGN] réseau de premier ordre
[Termes IGN] triangulation d'autres paysIndex. décimale : 30.32 Travaux de triangulation Numéro de notice : 64696 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=61380 Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 64696-01 30.32 Livre Centre de documentation En réserve M-103 Disponible 64696-02 30.32 Livre Centre de documentation En réserve M-103 Disponible The program for the 1993 adjustment of the Finnish first-order terrestrial triangulation / Jorma Jokela (1994)
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