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The development of integrated terrestrial and marine pathways in the Argo-Saronic region, Greece / J. M. L. Newhard in Cartography and Geographic Information Science, vol 41 n° 4 (September 2014)
[article]
Titre : The development of integrated terrestrial and marine pathways in the Argo-Saronic region, Greece Type de document : Article/Communication Auteurs : J. M. L. Newhard, Auteur ; N. S. Levine, Auteur ; A. D. Phebus, Auteur Année de publication : 2014 Article en page(s) : pp 379 - 390 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] âge du bronze
[Termes IGN] chemin le moins coûteux, algorithme du
[Termes IGN] Egée, mer
[Termes IGN] Grèce
[Termes IGN] voie de communicationRésumé : (auteur) Least cost path applications can be a powerful tool for understanding connectivity across a landscape. A limitation to this method is its difficulty in integrating terrestrial, marine, and cultural factors – all of which would have been at play in the prehistoric Aegean. This study looks at a method of modeling pathways that integrates major factors (land, sea, and culture) that would be in play while considering medium- to long-distance travel in the Aegean. This test case explores the possible relationships between proposed routes for communication and identified coastal sites with parameters modeled in geographic information system that affect travel in cultural, marine, and terrestrial contexts. The methods presented have significance beyond the Late Bronze Age Aegean. The development of a methodology that incorporates marine, cultural, and terrestrial environments provides a mechanism by which specific hypotheses regarding complex communication routes may be addressed in regions of the world where there is an intensive interplay between terrestrial and marine geographies. Numéro de notice : A2014-432 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/15230406.2014.925786 En ligne : https://doi.org/10.1080/15230406.2014.925786 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=73969
in Cartography and Geographic Information Science > vol 41 n° 4 (September 2014) . - pp 379 - 390[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-2014041 RAB Revue Centre de documentation En réserve L003 Disponible Active learning of user’s preferences estimation towards a personalized 3D navigation of geo-referenced scenes / Christos Yiakoumettis in Geoinformatica, vol 18 n° 1 (January 2014)
[article]
Titre : Active learning of user’s preferences estimation towards a personalized 3D navigation of geo-referenced scenes Type de document : Article/Communication Auteurs : Christos Yiakoumettis, Auteur ; Nikolaos Doulamis, Auteur ; Georgios Miaoulis, Auteur ; Djamchid Ghazanfarpour, Auteur Année de publication : 2014 Article en page(s) : pp 27 - 62 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] algorithme génétique
[Termes IGN] apprentissage dirigé
[Termes IGN] Athènes
[Termes IGN] exploration de données
[Termes IGN] itinéraire
[Termes IGN] métadonnées
[Termes IGN] navigation
[Termes IGN] ontologie
[Termes IGN] optimisation (mathématiques)
[Termes IGN] personnalisation
[Termes IGN] pondération
[Termes IGN] réalité virtuelle
[Termes IGN] système d'information géographique
[Termes IGN] utilisateurRésumé : (Auteur) The current technological evolutions enter 3D geo-informatics into their digital age, enabling new potential applications in the field of virtual tourism, pleasure, entertainment and cultural heritage. It is argued that 3D information provides the natural way of navigation. However, personalization is a key aspect in a navigation system, since a route that incorporates user preferences is ultimately more suitable than the route with the shortest distance or travel time. Usually, user’s preferences are expressed as a set of weights that regulate the degree of importance of the scene metadata on the route selection process. These weights, however, are defined by the users, setting the complexity to the user’s side, which makes personalization an arduous task. In this paper, we propose an alternative approach in which metadata weights are estimated implicitly and transparently to the users, transferring the complexity to the system side. This is achieved by introducing a relevance feedback on-line learning strategy which automatically adjusts metadata weights by exploiting information fed back to the system about the relevance of user’s preferences judgments given in a form of pair-wise comparisons. Practically implementing a relevance feedback algorithm presents the limitation that several pair-wise comparisons (samples) are required to converge to a set of reliable metadata weights. For this reason, we propose in this paper a weight rectification strategy that improves weight estimation by exploiting metadata interrelations defined through an ontology. In the sequel, a genetic optimization algorithm is incorporated to select the most user preferred routes based on a multi-criteria minimization approach. To increase the degree of personalization in 3D navigation, we have also introduced an efficient algorithm for estimating 3D trajectories around objects of interest by merging best selected 2D projected views that contain faces which are mostly preferred by the users. We have conducted simulations and comparisons with other approaches either in the field of on-line learning or route selection using objective metrics in terms of precision and recall values. The results indicate that our system yields on average a 13.76 % improvement of precision as regards the learning strategy and an improvement of 8.75 % regarding route selection. In addition, we conclude that the ontology driven weight rectification strategy can reduce the number of samples (pair-wise comparisons) required of 76 % to achieve the same precision. Qualitative comparisons have been also performed using a use case route scenario in the city of Athens. Numéro de notice : A2014-027 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10707-013-0176-0 Date de publication en ligne : 12/04/2013 En ligne : https://doi.org/10.1007/s10707-013-0176-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32932
in Geoinformatica > vol 18 n° 1 (January 2014) . - pp 27 - 62[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2014011 RAB Revue Centre de documentation En réserve L003 Disponible Sensitivity of spectral reflectance values to different burn and vegetation ratios: A multi-scale approach applied in a fire affected area / Magdalini Pleniou in ISPRS Journal of photogrammetry and remote sensing, vol 79 (May 2013)
[article]
Titre : Sensitivity of spectral reflectance values to different burn and vegetation ratios: A multi-scale approach applied in a fire affected area Type de document : Article/Communication Auteurs : Magdalini Pleniou, Auteur ; Nikos Koustias, Auteur Année de publication : 2013 Article en page(s) : pp 199 - 210 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] affinage d'image
[Termes IGN] analyse comparative
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] Grèce
[Termes IGN] image Ikonos
[Termes IGN] image Landsat-SWIR
[Termes IGN] image Terra-ASTER
[Termes IGN] incendie de forêt
[Termes IGN] rayonnement proche infrarouge
[Termes IGN] régression multiple
[Termes IGN] sol nuRésumé : (Auteur) The aim of our study was to explore the spectral properties of fire-scorched (burned) and non fire-scorched (vegetation) areas, as well as areas with different burn/vegetation ratios, using a multisource multiresolution satellite data set. A case study was undertaken following a very destructive wildfire that occurred in Parnitha, Greece, July 2007, for which we acquired satellite images from LANDSAT, ASTER, and IKONOS. Additionally, we created spatially degraded satellite data over a range of coarser resolutions using resampling techniques. The panchromatic (1 m) and multispectral component (4 m) of IKONOS were merged using the Gram-Schmidt spectral sharpening method. This very high-resolution imagery served as the basis to estimate the cover percentage of burned areas, bare land and vegetation at pixel level, by applying the maximum likelihood classification algorithm. Finally, multiple linear regression models were fit to estimate each land-cover fraction as a function of surface reflectance values of the original and the spatially degraded satellite images. The main findings of our research were: (a) the Near Infrared (NIR) and Short-wave Infrared (SWIR) are the most important channels to estimate the percentage of burned area, whereas the NIR and red channels are the most important to estimate the percentage of vegetation in fire-affected areas; (b) when the bi-spectral space consists only of NIR and SWIR, then the NIR ground reflectance value plays a more significant role in estimating the percent of burned areas, and the SWIR appears to be more important in estimating the percent of vegetation; and (c) semi-burned areas comprising 45–55% burned area and 45–55% vegetation are spectrally closer to burned areas in the NIR channel, whereas those areas are spectrally closer to vegetation in the SWIR channel. These findings, at least partially, are attributed to the fact that: (i) completely burned pixels present low variance in the NIR and high variance in the SWIR, whereas the opposite is observed in completely vegetated areas where higher variance is observed in the NIR and lower variance in the SWIR, and (ii) bare land modifies the spectral signal of burned areas more than the spectral signal of vegetated areas in the NIR, while the opposite is observed in SWIR region of the spectrum where the bare land modifies the spectral signal of vegetation more than the burned areas because the bare land and the vegetation are spectrally more similar in the NIR, and the bare land and burned areas are spectrally more similar in the SWIR. Numéro de notice : A2013-237 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.02.016 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.02.016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32375
in ISPRS Journal of photogrammetry and remote sensing > vol 79 (May 2013) . - pp 199 - 210[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013051 RAB Revue Centre de documentation En réserve L003 Disponible Catching data in the cobweb: an EU-wide project has just been set up to make it easier for citizens to collect environmental data for use in research, decision-making and creating public policy / Jamie Williams in GEO: Geoconnexion international, vol 12 n° 4 (april 2013)
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Titre : Catching data in the cobweb: an EU-wide project has just been set up to make it easier for citizens to collect environmental data for use in research, decision-making and creating public policy Type de document : Article/Communication Auteurs : Jamie Williams, Auteur Année de publication : 2013 Article en page(s) : pp 32 - 35 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique web
[Termes IGN] Allemagne
[Termes IGN] base de données localisées
[Termes IGN] données localisées des bénévoles
[Termes IGN] Grèce
[Termes IGN] Pays-Bas
[Termes IGN] plateforme collaborative
[Termes IGN] production participative
[Termes IGN] Royaume-Uni
[Termes IGN] science citoyenne
[Termes IGN] utilisateur civilRésumé : (Documentaliste) Le Cobweb (citizen observatory web) est une plate-forme d'externalisation ouverte ciblé sur le citoyen en tant que producteur, interprète et consommateur de données environnementales hétérogènes. Le Cobweb consortium cherche à appliquer un contrôle qualité de ces données et à en mesurer l'incertitude pour pouvoir les traiter. Numéro de notice : A2013-130 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/SOCIETE NUMERIQUE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32268
in GEO: Geoconnexion international > vol 12 n° 4 (april 2013) . - pp 32 - 35[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 062-2013041 SL Revue Centre de documentation Revues en salle Disponible DORIS and GPS monitoring of the Gavdos calibration site in Crete / Pascal Willis in Advances in space research, vol 51 n° 8 (April 2013)
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Titre : DORIS and GPS monitoring of the Gavdos calibration site in Crete Type de document : Article/Communication Auteurs : Pascal Willis , Auteur ; Stelios Mertikas, Auteur ; Donald F. Argus, Auteur ; Olivier Bock , Auteur Année de publication : 2013 Projets : Gavdos / Article en page(s) : pp 1438 - 1447 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] correction troposphérique
[Termes IGN] Crète (île)
[Termes IGN] étalonnage des données
[Termes IGN] GAMIT
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] modèle météorologique
[Termes IGN] positionnement par DORIS
[Termes IGN] positionnement par GPS
[Termes IGN] retard troposphérique zénithal
[Termes IGN] série temporelleRésumé : (auteur) Due to its specific geographical location as well as its geodetic equipment (DORIS, GNSS, microwave transponder and tide gauges), the Gavdos station in Crete, Greece is one of the very few sites around the world used for satellite altimetry calibration. To investigate the quality of the Gavdos geodetic coordinates and velocities, we analyzed and compared here DORIS and GPS-derived results obtained during several years of observations. The DORIS solution is the latest ignwd11 solution at IGN, expressed in ITRF2008, while the GPS solution was obtained using the GAMIT software package. Current results show that 1–2 mm/yr agreement can be obtained for 3-D velocity, showing a good agreement with current geophysical models. In particular, the agreement obtained for the vertical velocity is around 0.3–0.4 mm/yr, depending on the terrestrial reference frame. As a by-product of these geodetic GPS and DORIS results, Zenith Tropospheric Delays (ZTDs) estimations were also compared in 2010 between these two techniques, and compared to ECMWF values, showing a 6.6 mm agreement in dispersion without any significant difference between GPS and DORIS (with a 97.6% correlation), but with a 13–14 mm agreement in dispersion when comparing to ECMWF model (with only about 90% correlation for both techniques). These tropospheric delay estimations could also provide an external calibration of the tropospheric correction used for the geophysical data of satellite altimetry missions. Numéro de notice : A2013-798 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2012.08.006 En ligne : http://dx.doi.org/10.1016/j.asr.2012.08.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80125
in Advances in space research > vol 51 n° 8 (April 2013) . - pp 1438 - 1447[article]Mise en place d'un WebSIG de l'Île de Délos (Cyclades) / Q. Briquet in Géomatique expert, n° 87 (01/07/2012)PermalinkEstimation of the zero-height geopotential level WoLVD in a local vertical datum from inversion of co-located GPS, leveling and geoid heights: a case study in the Hellenic islands / Christopher Kotsakis in Journal of geodesy, vol 86 n° 6 (June 2012)PermalinkPermalinkCadastre à la grecque / Olivier Razemon in Géomètre, n° 2086 (novembre 2011)PermalinkUne leçon de topographie par correspondance : les lettres de l'ingénieur J. Foucherot et les levés du peintre L. F. S. Fauvel en Grèce / A. Zambon in Le monde des cartes, n° 207 (mars 2011)PermalinkAnalysis of long-term GPS observations in Greece (1993-2009) and geodynamic implications for the Eastern Mediterranean / Michael D. Müller (2011)PermalinkPermalinkL'utilisation des données spatiales dans l'étude du port antique d'Itanos (Crète orientale, Grèce) / Max Guy in Revue Française de Photogrammétrie et de Télédétection, n° 193 (Janvier 2011)PermalinkHellenic terrestrial reference system 2007 (HTRS07): a regional realization of ETRS89 over Greece in support of HEPOS / K. Katsampalos in Bulletin of geodesy and geomatics BGG, vol 69 n° 2 - 3 (December 2010)PermalinkSea surface topography and marine geoid by airborne laser altimetry and shipborne ultrasound altimetry / Philippe Limpach (2010)Permalink