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PerSE : visual analytics for calendar related spatiotemporal periodicity detection and analysis / Brian Swedberg in Geoinformatica, vol 21 n° 3 (July - September 2017)
[article]
Titre : PerSE : visual analytics for calendar related spatiotemporal periodicity detection and analysis Type de document : Article/Communication Auteurs : Brian Swedberg, Auteur ; Donna J. Peuquet, Auteur Année de publication : 2017 Article en page(s) : pp 577 - 597 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse visuelle
[Termes IGN] application web
[Termes IGN] calendrier
[Termes IGN] démonstration de faisabilité
[Termes IGN] dimension temporelle
[Termes IGN] exploration de données géographiques
[Termes IGN] filtrage d'information
[Termes IGN] fréquence
[Termes IGN] interactivité
[Termes IGN] sciences humaines et sociales
[Termes IGN] utilisateur
[Vedettes matières IGN] GéovisualisationRésumé : (Auteur) Periodicity is embedded in all societies. As most of us organize our lives based on temporal structures, it is hard to imagine what life would be like without it. We experience periodicity through naturally occurring rhythms that exist in nature, such as sunrise/sunset, seasonal changes in the weather, and the tides. We also experience it through abstract means via cultural, political, religious ties, such as the weekend, Independence Day, and Ramadan. Forms of periodicity, like the examples above, are foundational to making sense of human activity because they provide contextual rationale and frame normaility. However, disparate calendars (e.g. Islamic vs. Gregorian), localized idiosyncrasies, and other variables greatly complicate the analytical ability to uncover and understand human activity at a given time within a specified region. We have developed PerSE (Periodicity in Spatiotemporal Events): a web application designed to aid users in the detection and analysis of calendar related periodicity in spatiotemporal event data sets via exploratory user interaction. PerSE is composed of several crossfiltering views: the Map, Attribute View, Time-Wheel, Timeline, and Table. Users interactively set and release filters on one or more of the views to detect and analyze calendar related periodicity. This paper illustrates the utility of PerSE through an in-depth description of the tool and proof of concept usage example. Numéro de notice : A2017-382 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-016-0280-z En ligne : https://doi.org/10.1007/s10707-016-0280-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85813
in Geoinformatica > vol 21 n° 3 (July - September 2017) . - pp 577 - 597[article]Study and mitigation of calibration factor instabilities in a water vapor Raman lidar / Leslie David in Atmospheric measurement techniques, vol 10 n° 7 (July 2017)
[article]
Titre : Study and mitigation of calibration factor instabilities in a water vapor Raman lidar Type de document : Article/Communication Auteurs : Leslie David, Auteur ; Olivier Bock , Auteur ; Christian Thom , Auteur ; Pierre Bosser , Auteur ; Jacques Pelon, Auteur Année de publication : 2017 Projets : VEGAN / Bock, Olivier Article en page(s) : pp 2745 - 2758 Note générale : bibliographie
This work was developed in the framework of project VEGA and supported by the French national program LEFE/INSU.Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Atmosphère
[Termes IGN] azote
[Termes IGN] étalonnage d'instrument
[Termes IGN] fibre optique
[Termes IGN] lidar Raman
[Termes IGN] retard troposphérique
[Termes IGN] vapeur d'eauRésumé : (auteur) We have investigated calibration variations in the Rameau water vapor Raman lidar. This lidar system was developed by the Institut National de l'Information Géographique et Forestière (IGN) together with the Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS). It aims at calibrating Global Navigation Satellite System (GNSS) measurements for tropospheric wet delays and sounding the water vapor variability in the lower troposphere. The Rameau system demonstrated good capacity in retrieving water vapor mixing ratio (WVMR) profiles accurately in several campaigns. However, systematic short-term and long-term variations in the lidar calibration factor pointed to persistent instabilities. A careful testing of each subsystem independently revealed that these instabilities are mainly induced by mode fluctuations in the optic fiber used to couple the telescope to the detection subsystem and by the spatial nonuniformity of the photomultiplier photocathodes. Laboratory tests that replicate and quantify these instability sources are presented. A redesign of the detection subsystem is presented, which, combined with careful alignment procedures, is shown to significantly reduce the instabilities. Outdoor measurements were performed over a period of 5 months to check the stability of the modified lidar system. The calibration changes in the detection subsystem were monitored with lidar profile measurements using a common nitrogen filter in both Raman channels. A short-term stability of 2–3 % and a long-term drift of 2–3 % per month are demonstrated. Compared to the earlier Development of Methodologies for Water Vapour Measurement (DEMEVAP) campaign, this is a 3-fold improvement in the long-term stability of the detection subsystem. The overall water vapor calibration factors were determined and monitored with capacitive humidity sensor measurements and with GPS zenith wet delay (ZWD) data. The changes in the water vapor calibration factors are shown to be fairly consistent with the changes in the nitrogen calibration factors. The nitrogen calibration results can be used to correct the overall calibration factors without the need for additional water vapor measurements to within 1 % per month. Numéro de notice : A2017-868 Affiliation des auteurs : LASTIG LOEMI+Ext (2012-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/amt-10-2745-2017 Date de publication en ligne : 31/07/2017 En ligne : https://doi.org/10.5194/amt-10-2745-2017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89882
in Atmospheric measurement techniques > vol 10 n° 7 (July 2017) . - pp 2745 - 2758[article]Automatic measurement of control points for aerial image orientation / Adilson Berveglieri in Photogrammetric record, vol 32 n° 158 (June - july 2017)
[article]
Titre : Automatic measurement of control points for aerial image orientation Type de document : Article/Communication Auteurs : Adilson Berveglieri, Auteur ; Antonio Maria Garcia Tommaselli, Auteur Année de publication : 2017 Article en page(s) : pp 141 - 159 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] appariement d'images
[Termes IGN] calcul automatique
[Termes IGN] compensation par bloc
[Termes IGN] image aérienne
[Termes IGN] image terrestre
[Termes IGN] objectif grand angulaire
[Termes IGN] orientation d'image
[Termes IGN] point d'appui
[Termes IGN] précision des mesuresRésumé : (Auteur) This paper presents an automatic workflow for measuring natural ground control points (GCPs) in aerial images. The approach is based on the acquisition of multi-scale fisheye vertical terrestrial images over distinguishable areas to automatically generate georeferenced image patches. These are matched with aerial images using correspondence techniques and then used as ground control. The technique was assessed using a bundle block adjustment, indicating an accuracy based on check points of approximately 1/5 of the ground sample distance (GSD) in planimetry and 1 GSD in elevation. Automatic GCP measurements thus improved the final accuracy in comparison with manual measurement. Numéro de notice : A2017-362 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/phor.12190 En ligne : http:dx.doi.org/10.1111/phor.12190 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85773
in Photogrammetric record > vol 32 n° 158 (June - july 2017) . - pp 141 - 159[article]Copernicus Sentinel-2A calibration and products validation status / Ferran Gascon in Remote sensing, vol 9 n° 6 (June 2017)
[article]
Titre : Copernicus Sentinel-2A calibration and products validation status Type de document : Article/Communication Auteurs : Ferran Gascon, Auteur ; Catherine Bouzinac, Auteur ; Olivier Thépaut, Auteur ; Mathieu Jung, Auteur ; Benjamin Francesconi, Auteur ; Jérôme Louis, Auteur ; Vincent Lonjou, Auteur ; Bruno Lafrance, Auteur ; Stéphane Massera , Auteur ; et al., Auteur Année de publication : 2017 Projets : 1-Pas de projet / Bock, Olivier Article en page(s) : pp 1 - 81 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] constellation Sentinel
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] étalonnage géométrique
[Termes IGN] étalonnage radiométrique
[Termes IGN] image Sentinel-MSI
[Termes IGN] qualité des donnéesRésumé : (auteur) As part of the Copernicus programme of the European Commission (EC), the European Space Agency (ESA) has developed and is currently operating the Sentinel-2 mission that is acquiring high spatial resolution optical imagery. This article provides a description of the calibration activities and the status of the mission products validation activities after one year in orbit. Measured performances, from the validation activities, cover both Top-Of-Atmosphere (TOA) and Bottom-Of-Atmosphere (BOA) products. The presented results show the good quality of the mission products both in terms of radiometry and geometry and provide an overview on next mission steps related to data quality aspects. Numéro de notice : A2017-889 Affiliation des auteurs : IGN+Ext (2012-2019) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/rs9060584 Date de publication en ligne : 10/06/2017 En ligne : https://doi.org/10.3390/rs9060584 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91877
in Remote sensing > vol 9 n° 6 (June 2017) . - pp 1 - 81[article]Deformation monitoring of the submillimetric UPV calibration baseline / Luis García-Asenjo in Journal of applied geodesy, vol 11 n° 2 (June 2017)
[article]
Titre : Deformation monitoring of the submillimetric UPV calibration baseline Type de document : Article/Communication Auteurs : Luis García-Asenjo, Auteur ; Sergio Baselga, Auteur ; Pascual Garrigues, Auteur Année de publication : 2017 Article en page(s) : pp 107 - 114 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] base géodésique
[Termes IGN] déformation géométrique
[Termes IGN] distancemètre
[Termes IGN] étalonnage d'instrument
[Termes IGN] mécomètre
[Termes IGN] stabilité
[Termes IGN] Valence (Espagne)Résumé : (Auteur) A 330 m calibration baseline was established at the Universitat Politècnica de València (UPV) in 2007. Absolute scale was subsequently transferred in 2012 from the Nummela Standard Baseline in Finland and distances between pillars were determined with uncertainties ranging from 0.1 mm to 0.3 mm. In order to assess the long-term stability of the baseline, three field campaigns were carried out from 2013 to 2015 in a co-operative effort with the Universidad Complutense de Madrid (UCM), which provided the only Mekometer ME5000 distance meter available in Spain. Since the application of the ISO17123-4 full procedure did not suffice to come to a definite conclusion about possible displacements of the pillars, we opted for the traditional geodetic network approach. This approach had to be adapted to the case at hand in order to deal with problems such as the geometric weakness inherent to calibration baselines and scale uncertainty derived from both the use of different instruments and the high correlation between the meteorological correction and scale determination. Additionally, the so-called the maximum number of stable points method was also tested. In this contribution, it is described the process followed to assess the stability of the UPV submillimetric calibration baseline during the period of time from 2012 to 2015. Numéro de notice : A2017-284 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2016-0018 En ligne : https://doi.org/10.1515/jag-2016-0018 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85317
in Journal of applied geodesy > vol 11 n° 2 (June 2017) . - pp 107 - 114[article]Les géomètres du CERN et les faisceaux de particules / Dominique Missiaen in Géomètre, n° 2148 (juin 2017)PermalinkGPS code phase variations (CPV) for GNSS receiver antennas and their effect on geodetic parameters and ambiguity resolution / Tobias Kersten in Journal of geodesy, vol 91 n° 6 (June 2017)PermalinkUser testing of dynamic geovisualizations : lessons learned and possible improvements for cartographic experiments / Cécile Saint-Marc in International journal of cartography, vol 3 n° 1 (June 2017)PermalinkEvaluation of the range accuracy and the radiometric calibration of multiple terrestrial laser scanning instruments for data interoperability / Kim Calders in IEEE Transactions on geoscience and remote sensing, vol 55 n° 5 (May 2017)PermalinkLightweight UAV with on-board photogrammetry and single-frequency GPS positioning for metrology applications / Mehdi Daakir in ISPRS Journal of photogrammetry and remote sensing, vol 127 (May 2017)PermalinkUrban land use/land cover discrimination using image-based reflectance calibration methods for hyperspectral data / Shailesh S. Deshpande in Photogrammetric Engineering & Remote Sensing, PERS, vol 83 n° 5 (May 2017)PermalinkPerformance evaluation of GNSS-TEC estimation techniques at the grid point in middle and low latitudes during different geomagnetic conditions / O. E. Abe in Journal of geodesy, vol 91 n° 4 (April 2017)PermalinkAn evaluation of a visual analytics prototype for calendar-related spatiotemporal periodicity detection and analysis / Brian Swedberg in Cartographica, vol 52 n° 1 (Spring 2017)PermalinkSurveillance de santé structurale des ouvrages d’art incluant les systèmes de positionnement par satellites / Camille Favre in XYZ, n° 150 (mars - mai 2017)PermalinkCentimetric absolute localization using Unmanned Aerial Vehicles with airborne photogrammetry and on-board GPS / Mehdi Daakir (2017)Permalink