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Simulating SAR geometric distortions and predicting Persistent Scatterer densities for ERS-1/2 and ENVISAT C-band SAR and InSAR applications: Nationwide feasibility assessment to monitor the landmass of Great Britain with SAR imagery / Francesca Cigna in Remote sensing of environment, vol 152 (September 2014)
[article]
Titre : Simulating SAR geometric distortions and predicting Persistent Scatterer densities for ERS-1/2 and ENVISAT C-band SAR and InSAR applications: Nationwide feasibility assessment to monitor the landmass of Great Britain with SAR imagery Type de document : Article/Communication Auteurs : Francesca Cigna, Auteur ; Luke B. Bateson, Auteur ; Colm J. Jordan, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 441 - 466 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] coin réflecteur
[Termes IGN] distorsion d'image
[Termes IGN] effondrement de terrain
[Termes IGN] étude de faisabilité
[Termes IGN] Grande-Bretagne
[Termes IGN] image Envisat-ASAR
[Termes IGN] image ERS-SAR
[Termes IGN] image radar moirée
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] risque naturel
[Termes IGN] simulationIndex. décimale : 35.43 Applications de télédétection - géologie Résumé : (auteur) We assess the feasibility of monitoring the landmass of Great Britain with satellite Synthetic Aperture Radar (SAR) imagery, by analysing ERS-1/2 SAR and ENVISAT IS2 Advanced SAR (ASAR) archive data availability, geometric distortions and land cover control on the success of (non-)interferometric analyses. Our assessment both addresses the scientific and operational question ofwhether a nationwide SAR-based monitoring of ground motion would succeed in Great Britain, and helps to understand controlling factors and possible solutions to overcome the limitations of undertaking SAR-based imaging of the landmass. This is the first time such a nationwide assessment is performed in preparation for acquisition and processing of SAR data in the United Kingdom, and any other country in the world. Analysis of the ERS-1/2 and ENVISAT archives reveals potential for multi-interferogram SAR Interferometry (InSAR) for the entirety of Britain using ERS-1/2 in descending mode, with 100% standard image frames showing at least 20 archive scenes available. ERS-1/2 ascending and both ENVISAT modes show potential for non-interferometric and single-pair InSAR for the vast majority of Britain, and multi-interferogram only for 13% to 38% of the available standard frames. Based on NEXTMap® Britain Digital Terrain Model (DTM) we simulate SAR layover, foreshortening and shadow to the ERS-1/2 and ENVISAT Lines-Of-Sight (LOS), and quantify changes of SAR distortions with variations in mode, LOS incidence angles and ground track angles, local terrain orientation, and the effect of scale due to the input DTM resolution. The simulation is extended to the ~230,000 km2 landmass, and shows limited control of local topography on the radar terrain visibility. According to the 50m to 5m DTM-based simulations, ~1.0–1.4% of Great Britain could potentially be affected by shadowand layover in eachmode. Only ~0.02–0.04% overlapping between ascending and descending mode distortions is found, this indicating the negligible proportion of the landmass that cannot be monitored using either imaging mode. We calibrate the CORINE Land Cover 2006 (CLC2006) using Persistent Scatterer (PS) datasets available for London, Stoke-On-Trent, Newcastle and Bristol, to quantify land cover control on the PS distribution and characterize the CLC2006 classes in terms of the potential PS density they could provide. Despite predominance of rural land cover types, we predict potential for over 12.8 M monitoring targets for each acquisition mode using a set of image frames covering the entire landmass. We validate our assessment by processing with the Interferometric Point Target Analysis (IPTA) 55 ERS-1/2 SAR scenes depicting South Wales between 1992 and 1999. Although absolute differences between predicted and observed target density are revealed, relative densities and rankings among the various CLC2006 classes are found constant across the calibration and validation datasets. Rescaled predictions for Britain show potential for a total of 2.5M monitoring targets across the landmass. We examine the use of the topographic and land cover feasibility maps for landslide studies in relation to the British Geological Survey's National Landslide Database and DiGMapGB mass movement layer. Building upon recent literature, we finally discuss future perspectives relating to the replication of our feasibility assessment to account for higher resolution SAR imagery, new Earth explorers (e.g., Sentinel-1) and improved processing techniques, showing potential to generate invaluable sources of information on land motions and geohazards in Great Britain. Numéro de notice : A2014-452 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2014.06.025 Date de publication en ligne : 05/08/2014 En ligne : https://doi.org/10.1016/j.rse.2014.06.025 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74014
in Remote sensing of environment > vol 152 (September 2014) . - pp 441 - 466[article]Documents numériques
en open access
A2014-452 simulating SAR geometric distorsions_CignaAdobe Acrobat PDF Studying commuting behaviours using collaborative visual analytics / Roger Beecham in Computers, Environment and Urban Systems, vol 47 (September 2014)
[article]
Titre : Studying commuting behaviours using collaborative visual analytics Type de document : Article/Communication Auteurs : Roger Beecham, Auteur ; Jo Wood, Auteur ; Audrey Bowerman, Auteur Année de publication : 2014 Article en page(s) : pp 5 - 15 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse géovisuelle
[Termes IGN] analyse spatio-temporelle
[Termes IGN] cycliste
[Termes IGN] densité des points
[Termes IGN] estimation par noyau
[Termes IGN] Londres
[Termes IGN] migration pendulaire
[Termes IGN] mobilité urbaine
[Termes IGN] origine - destination
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) Mining a large origin–destination dataset of journeys made through London’s Cycle Hire Scheme (LCHS), we develop a technique for automatically classifying commuting behaviour that involves a spatial analysis of cyclists’ journeys. We identify a subset of potential commuting cyclists, and for each individual define a plausible geographic area representing their workplace. All peak-time journeys terminating within the vicinity of this derived workplace in the morning, and originating from this derived workplace in the evening, we label commutes. Three techniques for creating these workplace areas are compared using visual analytics: a weighted mean-centres calculation, spatial k-means clustering and a kernel density-estimation method. Evaluating these techniques at the individual cyclist level, we find that commuters’ peak-time journeys are more spatially diverse than might be expected, and that for a significant portion of commuters there appears to be more than one plausible spatial workplace area. Evaluating the three techniques visually, we select the density-estimation as our preferred method. Two distinct types of commuting activity are identified: those taken by LCHS customers living outside of London, who make highly regular commuting journeys at London’s major rail hubs; and more varied commuting behaviours by those living very close to a bike-share docking station. We find evidence of many interpeak journeys around London’s universities apparently being taken as part of cyclists’ working day. Imbalances in the number of morning commutes to, and evening commutes from, derived workplaces are also found, which might relate to local availability of bikes. Significant decisions around our workplace analysis, and particularly these broader insights into commuting behaviours, are discovered through exploring this analysis visually. The visual analysis approach described in the paper is effective in enabling a research team with varying levels of analysis experience to participate in this research. We suggest that such an approach is of relevance to many applied research contexts. Numéro de notice : A2014-798 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/URBANISME Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.compenvurbsys.2013.10.007 En ligne : http://dx.doi.org/10.1016/j.compenvurbsys.2013.10.007 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82467
in Computers, Environment and Urban Systems > vol 47 (September 2014) . - pp 5 - 15[article]A conceptual framework for creating cartographic representations in SDI environments / Anja Hopfstock in Cartographic journal (the), vol 50 n° 4 (November 2013)
[article]
Titre : A conceptual framework for creating cartographic representations in SDI environments Type de document : Article/Communication Auteurs : Anja Hopfstock, Auteur ; Manfred F. Buchroithner, Auteur ; Dietmar Grünreich, Auteur Année de publication : 2013 Article en page(s) : pp 345 - 355 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie
[Termes IGN] conception cartographique
[Termes IGN] conception orientée utilisateur
[Termes IGN] données localisées de référence
[Termes IGN] infrastructure européenne de données localisées
[Termes IGN] infrastructure nationale des données localisées
[Termes IGN] représentation cartographique
[Termes IGN] Royaume-UniRésumé : (Auteur) The low awareness of the communication function of maps within the Geospatial Data Infrastructure (SDI) community has prompted PhD research (Hopfstock, 2010) to explore how the concept of user-oriented map design can be utilized to improve the SDI usability for end users. In particular, the research aimed at providing a methodology for creating effective cartographic representations and design solutions for SDI relevant user types that facilitate gaining useful Geographic Information (GI) at the interface between SDI and their users as a result of the map viewing and interpretation process. This paper outlines the empirical research and highlights the main findings. Numéro de notice : A2013-686 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/1743277413Y.0000000033 En ligne : https://doi.org/10.1179/1743277413Y.0000000033 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32822
in Cartographic journal (the) > vol 50 n° 4 (November 2013) . - pp 345 - 355[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 030-2013041 RAB Revue Centre de documentation En réserve L003 Disponible The military map of the United Kingdom and its impact on mapping in the twentieth century / Peter Collier in Cartographic journal (the), vol 50 n° 4 (November 2013)
[article]
Titre : The military map of the United Kingdom and its impact on mapping in the twentieth century Type de document : Article/Communication Auteurs : Peter Collier, Auteur Année de publication : 2013 Article en page(s) : pp 324 - 331 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie ancienne
[Termes IGN] carte militaire
[Termes IGN] cartographie ancienne
[Termes IGN] cartographie étrangère
[Termes IGN] dix-neuvième siècle
[Termes IGN] histoire de la cartographie
[Termes IGN] Ordnance Survey (UK)
[Termes IGN] représentation cartographique
[Termes IGN] Royaume-Uni
[Termes IGN] style cartographique
[Termes IGN] vingtième siècleRésumé : (Auteur) Considerable attention has been paid in the literature to the changing style of Ordnance Survey mapping in the twentieth century. However, little has been written about the origins of the characteristic appearance of the first multi-colour editions, other that the Ordnance Survey used a military edition that was already in production. The distinctive style grew out of the work of a committee established in 1892 by the War Office to consider future army requirements for a map of the UK. This paper explores the work of the committee and its long-term implications for the look of mapping in the twentieth century. Numéro de notice : A2013-684 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/1743277412Y.0000000023 En ligne : https://doi.org/10.1179/1743277412Y.0000000023 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32820
in Cartographic journal (the) > vol 50 n° 4 (November 2013) . - pp 324 - 331[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 030-2013041 RAB Revue Centre de documentation En réserve L003 Disponible Adaptive zoning for transport mode choice modeling / Alex Hagen-Zanker in Transactions in GIS, vol 17 n° 5 (October 2013)
[article]
Titre : Adaptive zoning for transport mode choice modeling Type de document : Article/Communication Auteurs : Alex Hagen-Zanker, Auteur ; Ying Jin, Auteur Année de publication : 2013 Article en page(s) : pp 706 - 723 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] extensibilité
[Termes IGN] interaction spatiale
[Termes IGN] Londres
[Termes IGN] modélisation spatiale
[Termes IGN] outil d'aide à la décision
[Termes IGN] réseau de transport
[Termes IGN] zonage (urbanisme)Résumé : (Auteur) Adaptive zoning is a recently introduced method for improving computer modeling of spatial interactions and movements in the transport network. Unlike traditional zoning, where geographic locations are defined by one single universal plan of discrete land parcels or ‘zones’ for the study area, adaptive zoning establishes a compendium of different zone plans, each of which is applicable to one journey origin or destination only. These adaptive zone plans are structured to represent strong spatial interactions in proportionately more detail than weaker ones. In recent articles, it has been shown that adaptive zoning improves, by a large margin, the scalability of models of spatial interaction and road traffic assignment. This article confronts the method of adaptive zoning with an application of the scale and complexity for which it was intended, namely an application of mode choice modeling that at the same time requires a large study area and a fine-grained zone system. Our hypothesis is that adaptive zoning can significantly improve the accuracy of mode choice modeling because of its enhanced sensitivity to the geographic patterns and scales of spatial interaction. We test the hypothesis by investigating the performance of three alternative models: (1) a spatially highly detailed model that is permissible to the maximum extent by available data, but requires a high computational load that is generally out of reach for rapid turnaround of policy studies; (2) a mode choice model for the same area, but reducing the computational load by 90% by using a traditional zone system consisting of fewer zones; and (3) a mode choice model that also reduces the computational load by 90%, but based on adaptive zoning instead. The tests are carried out on the basis of a case study that uses the dataset from the London Area Transport Survey. Using the first model as a benchmark, it is found that for a given computational load, the model based on adaptive zoning contains about twice the amount of information of the traditional model, and model parameters on adaptive zoning principles are more accurate by a factor of six to eight. The findings suggest that adaptive zoning has a significant potential in enhancing the accuracy of mode choice modeling at the city or city-region scale. Numéro de notice : A2013-578 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/j.1467-9671.2012.01372.x Date de publication en ligne : 14/01/2013 En ligne : https://doi.org/10.1111/j.1467-9671.2012.01372.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32714
in Transactions in GIS > vol 17 n° 5 (October 2013) . - pp 706 - 723[article]How reliable are citizen-derived scientific data? Assessing the quality of contrail observations made by the general public / Amy Fowler in Transactions in GIS, vol 17 n° 4 (August 2013)PermalinkTemporal uncertainty in a small area open geodemographic classification / Christopher G. Gale in Transactions in GIS, vol 17 n° 4 (August 2013)PermalinkL'acceptation de l'élément marin dans la gestion du trait de côte : une nouvelle gouvernance face au risque de submersion ? Les cas du Lincolnshire, de l'Essex (Angleterre), du littoral picard et du bassin d'Arcachon (France) / Vincent Bawedin in Annales de géographie, n° 692 (juillet - août 2013)PermalinkLauching the satellite applications Catapult / Stuart Martin in GEO: Geoconnexion international, vol 12 n° 5 (may 2013)PermalinkCatching 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)PermalinkA change detection approach to flood mapping in urban areas using TerraSAR-X / Laura Giustrarini in IEEE Transactions on geoscience and remote sensing, vol 51 n° 4 Tome 2 (April 2013)PermalinkPermalinkNational importance / C. Mccormack in GEO: Geoconnexion international, vol 12 n° 3 (march 2013)PermalinkThe art of the noise / N. Thurston in GEO: Geoconnexion international, vol 12 n° 3 (march 2013)PermalinkPermalink