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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)
[article]
Titre : How reliable are citizen-derived scientific data? Assessing the quality of contrail observations made by the general public Type de document : Article/Communication Auteurs : Amy Fowler, Auteur ; J. Duncan Whyatt, Auteur ; Gemma Davies, Auteur ; Rebecca Ellis, Auteur Année de publication : 2013 Article en page(s) : pp 488 - 506 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] Angleterre
[Termes IGN] atmosphère terrestre
[Termes IGN] condensation
[Termes IGN] données localisées des bénévoles
[Termes IGN] données météorologiques
[Termes IGN] données multisources
[Termes IGN] fiabilité des données
[Termes IGN] grand public
[Termes IGN] science citoyenneRésumé : (Auteur) Citizen science projects encourage the general public to participate in scientific research. Participants can contribute large volumes of data over broad spatial and temporal frames; however, the challenge is to generate data of sufficient quality to be useable in scientific research. Most observations made by citizen-scientists can be independently verified by “experts”. However, verification is more problematic when the phenomena being recorded are short-lived. This article uses a GIS methodology to verify the quality of contrail observations made by the general public as part of the OPAL Climate Survey. We verify observations using datasets derived from a variety of different sources (experts, models and amateur enthusiasts) with different spatial and temporal properties which reflect the complex 3D nature of the atmosphere. Our results suggest that ~70% of citizen observations are plausible, based on favorable atmospheric conditions and the presence or absence of aircraft; a finding which is in keeping with other, more conventional citizen science projects. However, questions remain as to why the quality of the citizen-based observations was so high. Given the lack of supporting data on observers, it is impossible to determine whether the dataset was generated by the activities of many participants or a small but dedicated number of individual observers. Numéro de notice : A2013-468 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE/SOCIETE NUMERIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12034 Date de publication en ligne : 22/05/2013 En ligne : https://doi.org/10.1111/tgis.12034 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32606
in Transactions in GIS > vol 17 n° 4 (August 2013) . - pp 488 - 506[article]Temporal uncertainty in a small area open geodemographic classification / Christopher G. Gale in Transactions in GIS, vol 17 n° 4 (August 2013)
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Titre : Temporal uncertainty in a small area open geodemographic classification Type de document : Article/Communication Auteurs : Christopher G. Gale, Auteur ; Paul A. Longley, Auteur Année de publication : 2013 Article en page(s) : pp 563 - 588 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] analyse diachronique
[Termes IGN] classification
[Termes IGN] données démographiques
[Termes IGN] exploration de données géographiques
[Termes IGN] incertitude temporelle
[Termes IGN] Royaume-UniRésumé : (Auteur) The 2001 Output Area Classification (2001 OAC) is an open source geodemographic classification of the UK built exclusively from 2001 UK Census data. There has been considerable user interest in its applicability to subsequent time periods, particularly given the potential propensity of characteristics and attributes in some areas to change during inter-censual periods. Users often purchase commercial geodemographic classification products in the belief that purely census-based classifications such as the 2001 OAC are uniformly unreliable because there is no temporal updating of input data. Yet there is evidence to suggest that whilst some UK neighborhoods are prone to sudden changes, many others change very little over protracted time periods. Using measures that are available at the small area level, temporal uncertainty indicators can be constructed to identify those areas that are less stable. Using mid-year population estimates and dwelling stock data, this article develops three temporal uncertainty indicators. These provide a reliable means of gauging the stability or otherwise of neighborhood conditions. The conclusion from this is that while a large number of small areas in the UK do experience change over time, this change is not uniform in either degree or distribution, or by geodemographic type. Numéro de notice : A2013-472 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12035 Date de publication en ligne : 23/05/2013 En ligne : https://doi.org/10.1111/tgis.12035 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32610
in Transactions in GIS > vol 17 n° 4 (August 2013) . - pp 563 - 588[article]Topologically safe curved schematisation / Arthur Van Goethem in Cartographic journal (the), vol 50 n° 3 (August 2013)
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Titre : Topologically safe curved schematisation Type de document : Article/Communication Auteurs : Arthur Van Goethem, Auteur ; Wouter Meulemans, Auteur ; Andreas W. Reimer, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 276 - 285 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] courbe
[Termes IGN] courbe de Bézier
[Termes IGN] diagramme de Voronoï
[Termes IGN] généralisation automatique de données
[Termes IGN] généralisation cartographique automatisée
[Termes IGN] intégrité topologique
[Termes IGN] simplification de contourRésumé : (Auteur) Traditionally schematised maps make extensive use of curves. However, automated methods for schematisation are mostly restricted to straight lines. We present a generic framework for topology-preserving curved schematisation that allows a choice of quality measures and curve types. The framework fits a curve to every part of the input. It uses Voronoi diagrams to ensure that curves fitted to disjoint parts do not intersect. The framework then employs a dynamic program to find an optimal schematisation using the fitted curves. Our fully-automated approach does not need critical points or salient features. We illustrate our framework with Bézier curves and circular arcs. Numéro de notice : A2013-467 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/1743277413Y.0000000066 En ligne : https://doi.org/10.1179/1743277413Y.0000000066 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32605
in Cartographic journal (the) > vol 50 n° 3 (August 2013) . - pp 276 - 285[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 030-2013031 RAB Revue Centre de documentation En réserve L003 Disponible Index-based query processing on distributed multidimensional data / George Tsatsanifos in Geoinformatica, vol 17 n° 3 (July 2013)
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Titre : Index-based query processing on distributed multidimensional data Type de document : Article/Communication Auteurs : George Tsatsanifos, Auteur ; Dimitri Sacharidis, Auteur ; Timos Sellis, Auteur Année de publication : 2013 Article en page(s) : pp 489 - 519 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] base de données répartie
[Termes IGN] données multidimensionnelles
[Termes IGN] index spatial
[Termes IGN] requête spatialeRésumé : (Auteur) This work introduces decentralized query processing techniques based on MIDAS, a novel distributed multidimensional index. In particular, MIDAS implements a distributed k-d tree, where leaves correspond to peers, and internal nodes dictate message routing. MIDAS requires that peers maintain little network information, and features mechanisms that support fault tolerance and load balancing. The proposed algorithms process point and range queries over the multidimensional indexed space in only O(log n) hops in expectance, where n is the network size. For nearest neighbor queries, two processing alternatives are discussed. The first, termed eager processing, has low latency (expected value of O(log n) hops) but may involve a large number of peers. The second, termed iterative processing, has higher latency (expected value of O(log2 n) hops) but involves far fewer peers. A detailed experimental evaluation demonstrates that our query processing techniques outperform existing methods for settings involving real spatial data as well as in the case of high dimensional synthetic data. Numéro de notice : A2013-383 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-012-0163-x Date de publication en ligne : 09/08/2012 En ligne : https://doi.org/10.1007/s10707-012-0163-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32521
in Geoinformatica > vol 17 n° 3 (July 2013) . - pp 489 - 519[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2013031 RAB Revue Centre de documentation En réserve L003 Disponible
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Titre : Spatial inverse query processing Type de document : Article/Communication Auteurs : Thomas Bernecker, Auteur ; Tobias Emrich, Auteur ; Hans-Peter Kriegel, Auteur ; Nikos Mamoulis, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 449 - 487 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] plus proche voisin, algorithme du
[Termes IGN] requête spatiale
[Termes IGN] requête spatiale inverseRésumé : (Auteur) Traditional spatial queries return, for a given query object q, all database objects that satisfy a given predicate, such as epsilon range and k-nearest neighbors. This paper defines and studies inverse spatial queries, which, given a subset of database objects Q and a query predicate, return all objects which, if used as query objects with the predicate, contain Q in their result. We first show a straightforward solution for answering inverse spatial queries for any query predicate. Then, we propose a filter-and-refinement framework that can be used to improve efficiency. We show how to apply this framework on a variety of inverse queries, using appropriate space pruning strategies. In particular, we propose solutions for inverse epsilon range queries, inverse k-nearest neighbor queries, and inverse skyline queries. Furthermore, we show how to relax the definition of inverse queries in order to ensure non-empty result sets. Our experiments show that our framework is significantly more efficient than naive approaches. Numéro de notice : A2013-382 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-012-0162-y Date de publication en ligne : 24/08/2012 En ligne : https://doi.org/10.1007/s10707-012-0162-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32520
in Geoinformatica > vol 17 n° 3 (July 2013) . - pp 449 - 487[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2013031 RAB Revue Centre de documentation En réserve L003 Disponible Une adresse normalisée sur toute la France / Pierre Clergeot in Géomètre, n° 2104 (juin 2013)PermalinkAssessing the effect of data imports on the completeness of OpenStreetMap: a United States case study / Dennis Zielstra in Transactions in GIS, vol 17 n° 3 (June 2013)PermalinkImproving representation of land-use maps derived from object-oriented image classification / Wenxiu Gao in Transactions in GIS, vol 17 n° 3 (June 2013)PermalinkScaleMaster 2.0: a ScaleMaster extension to monitor automatic multi-scales generalizations / Guillaume Touya in Cartography and Geographic Information Science, vol 40 n° 3 (June 2013)PermalinkUsing reverse viewshed analysis to assess the location correctness of visually generated VGI / Hansi Senaratne in Transactions in GIS, vol 17 n° 3 (June 2013)PermalinkMulti-level representation of terrain features on a contour map / Eric Guilbert in Geoinformatica, vol 17 n° 2 (April 2013)PermalinkSTHist-C: a highly accurate cluster-based histogram for two and three dimensional geographic data points / Hai Thanh Mai in Geoinformatica, vol 17 n° 2 (April 2013)PermalinkAnalyse de données spatiotemporelles imparfaites dans un SIG archéologique / Cyril de Runz in Cartes & Géomatique, n° 215 (mars 2013)PermalinkEstimation de l'imprécision des mesures géométriques de longueur et de surface / Jean-François Girres in Cartes & Géomatique, n° 215 (mars 2013)PermalinkModèles et méthodes pour l'information spatio-temporelle évolutive / Christine Plumejeaud in Cartes & Géomatique, n° 215 (mars 2013)Permalink