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Using cover measurements to estimate aboveground understorey biomass in Maritime pine stands / Annabel J. Porté in Annals of Forest Science, Vol 66 n° 3 (April - May 2009)
[article]
Titre : Using cover measurements to estimate aboveground understorey biomass in Maritime pine stands Titre original : Estimation de la biomasse aérienne du sous-bois de peuplements de pin maritime à l'aide de mesures de recouvrement Type de document : Article/Communication Auteurs : Annabel J. Porté, Auteur ; Jean-Charles Samalens, Auteur ; Raphaël Dulhoste, Auteur ; Rémi Teissier du Cros, Auteur ; Alexandre Bosc, Auteur ; Céline Meredieu, Auteur Année de publication : 2009 Article en page(s) : n° 307 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] biomasse forestière
[Termes IGN] mise à l'échelle
[Termes IGN] modèle de croissance végétale
[Termes IGN] Pinus pinaster
[Termes IGN] sous-boisRésumé : (auteur) Understorey plays a major role in forest fluxes and stocks balances, however this compartment is generally poorly quantified. Our objectives were to establish models to estimate understorey biomass using vegetation cover measurements and to investigate upscaling methodologies from stand to regional level. Understorey aboveground biomass measurements were undertaken in Maritime pine stands of mesohygric, mesic and dry moorlands in South West France. Average biomass stock in this compartment was estimated to 3.50 t DM ha-1. The more abundant species groups varied with moorland types, with a higher relative contribution of herbaceous species (23.3%), bracken (59.2%) and mosses (31.6%) for mesohygric, mesic and dry moorlands, respectively. For each species group, we established significant relationships to estimate biomass using a volumetric index, based on cover and height measurements. No relationship between stand characteristics and understorey biomass was founded. We investigated the upscaling of these estimations to a several thousands hectare area using understorey cover measurements done along a regular spatial grid. The only significant correlation linked one satellite vegetation index to understorey biomass. We successfully developed empirical relationships to estimate the understorey biomass at the stand level. Further investigations could focus on the analysis of understorey variability over a finer space grid and the potential use of satellite vegetation indexes. Numéro de notice : A2009-710 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1051/forest/2009005 Date de publication en ligne : 10/03/2009 En ligne : https://www.afs-journal.org/articles/forest/full_html/2009/03/f08135/f08135.html Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=72062
in Annals of Forest Science > Vol 66 n° 3 (April - May 2009) . - n° 307[article]An automated method of scale selection and sheet configuration for multiple sheet census maps with Insets / W.G. Thompson in Cartography and Geographic Information Science, vol 36 n° 1 (January 2009)
[article]
Titre : An automated method of scale selection and sheet configuration for multiple sheet census maps with Insets Type de document : Article/Communication Auteurs : W.G. Thompson, Auteur Année de publication : 2009 Article en page(s) : pp 59 - 70 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie thématique
[Termes IGN] analyse de groupement
[Termes IGN] cartographie automatique
[Termes IGN] carton (carte)
[Termes IGN] densité de population
[Termes IGN] échelle cartographique
[Termes IGN] mise à l'échelleRésumé : (Auteur) In order to create a useful map, the cartographer must select a scale at which the map reader can distinguish features shown on the map and read their labels. However, the choice of scale for a paper map is also constrained by the size of the map sheet and by the cost of working with a large number of sheets. When the feature density pattern allows, space can be conserved by making the map at more than one scale: a small scale suitable for most of the map, while dense features are shown on inset maps at larger scales. Creating inset maps requires the cartographer to make a series of complex, interrelated decisions regarding the most effective overall sheet configuration, which is dependent upon the scale chosen for the main map and how the inset maps are created. The Census Automated Map Production System (CAMPS) applies cartographic logic and density analysis to make these decisions in a fully automated mapping environment. Copyright CaGISociety Numéro de notice : A2009-041 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1559/152304009787340214 En ligne : https://doi.org/10.1559/152304009787340214 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29671
in Cartography and Geographic Information Science > vol 36 n° 1 (January 2009) . - pp 59 - 70[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-09011 RAB Revue Centre de documentation En réserve L003 Disponible The effect of instructions on distance and similarity judgements in information spatializations / Sara Irina Fabrikant in International journal of geographical information science IJGIS, vol 22 n° 4-5 (april 2008)
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Titre : The effect of instructions on distance and similarity judgements in information spatializations Type de document : Article/Communication Auteurs : Sara Irina Fabrikant, Auteur ; Daniel R. Montello, Auteur Année de publication : 2008 Article en page(s) : pp 463 - 478 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie
[Termes IGN] détail topographique
[Termes IGN] distance euclidienne
[Termes IGN] représentation cognitive
[Termes IGN] similitude
[Termes IGN] visualisation de donnéesRésumé : (Auteur) We investigate the relationship of perceived distances to judged similarities between document points in various types of spatialized displays. Our findings suggest that the distance-similarity relationship is not as self-evident to viewers as is commonly assumed in the information visualization literature. We further investigate how participants interpret instructions to judge distances when those instructions do or do not specify the type of distance. We find that in all types of spatialization displays, there is no significant difference between default and direct judgements of distance; people clearly interpret default distance instructions to refer to direct (straight-line) distance. These findings provide direct evidence on the conditions under which people employ distance when assessing similarity between data objects in various types of spatialized views and, when they do, which type of distance. They also give insight into how people explore the similarity of geographic features depicted in cartographic maps or GIS displays. Copyright Taylor & Francis Numéro de notice : A2008-150 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810701517096 En ligne : https://doi.org/10.1080/13658810701517096 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29145
in International journal of geographical information science IJGIS > vol 22 n° 4-5 (april 2008) . - pp 463 - 478[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-08031 RAB Revue Centre de documentation En réserve L003 Disponible 079-08032 RAB Revue Centre de documentation En réserve L003 Disponible Transforming ellipsoidal heights and geoid undulations between different geodetic reference frames / Christopher Kotsakis in Journal of geodesy, vol 82 n° 4-5 (April - May 2008)
[article]
Titre : Transforming ellipsoidal heights and geoid undulations between different geodetic reference frames Type de document : Article/Communication Auteurs : Christopher Kotsakis, Auteur Année de publication : 2008 Article en page(s) : pp 249 - 260 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] coordonnées cartésiennes
[Termes IGN] coordonnées curvilignes
[Termes IGN] ellipsoïde de référence
[Termes IGN] géoïde gravimétrique
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] repère de référence
[Termes IGN] similitude
[Termes IGN] transformation de HelmertRésumé : (Auteur) Transforming height information that refers to an ellipsoidal Earth reference model, such as the geometric heights determined from GPS measurements or the geoid undulations obtained by a gravimetric geoid solution, from one geodetic reference frame (GRF) to another is an important task whose proper implementation is crucial for many geodetic, surveying and mapping applications. This paper presents the required methodology to deal with the above problem when we are given the Helmert transformation parameters that link the underlying Cartesian coordinate systems to which an Earth reference ellipsoid is attached. The main emphasis is on the effect of GRF spatial scale differences in coordinate transformations involving reference ellipsoids, for the particular case of heights. Since every three-dimensional Cartesian coordinate system ‘gauges’ an attached ellipsoid according to its own accessible scale, there will exist a supplementary contribution from the scale variation between the involved GRFs on the relative size of their attached reference ellipsoids. Neglecting such a scale-induced indirect effect corrupts the values for the curvilinear geodetic coordinates obtained from a similarity transformation model, and meter-level apparent offsets can be introduced in the transformed heights. The paper explains the above issues in detail and presents the necessary mathematical framework for their treatment. Copyright Springer Numéro de notice : A2008-169 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-007-0179-4 En ligne : https://doi.org/10.1007/s00190-007-0179-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29164
in Journal of geodesy > vol 82 n° 4-5 (April - May 2008) . - pp 249 - 260[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-08042 RAB Revue Centre de documentation En réserve L003 Disponible 266-08041 RAB Revue Centre de documentation En réserve L003 Disponible A comparison of geometric approaches to assessing spatial similarity for GIR / P. Frontiera in International journal of geographical information science IJGIS, vol 22 n° 3 (march 2008)
[article]
Titre : A comparison of geometric approaches to assessing spatial similarity for GIR Type de document : Article/Communication Auteurs : P. Frontiera, Auteur ; R. Larson, Auteur ; J. Radke, Auteur Année de publication : 2008 Article en page(s) : pp 337 - 360 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données
[Termes IGN] approximation
[Termes IGN] indexation spatiale
[Termes IGN] pertinence
[Termes IGN] recherche d'information géographique
[Termes IGN] requête spatiale
[Termes IGN] similitudeRésumé : (Auteur) This research compares the geographic information retrieval (GIR) performance of a set of logistic regression models with those of five non-probabilistic methods that compute a spatial similarity score for a query-document pair. All methods are applied to a test collection of queries and documents indexed spatially by two convex conservative geometric approximations: the minimum bounding box (MBB) and the convex hull. In the comparison, the tested logistic regression models outperform, in terms of standard information retrieval recall and precision measures, all of the non-probabilistic methods. The retrieval performance achieved by the logistic regression models on MBB approximations is similar to that achieved by the use of the non-probabilistic methods on convex hulls. Although these results are valid only for the test collection used in this study, they suggest that a logistic regression approach to GIR provides an alternative to the use of higher-quality geometric representations that are more difficult to obtain, implement, and process. Additionally, this research demonstrates the ability of a probabilistic approach to effectively incorporate information about geographic context in the spatial ranking process. Copyright Taylor & Francis Numéro de notice : A2008-143 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810701626293 En ligne : https://doi.org/10.1080/13658810701626293 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29138
in International journal of geographical information science IJGIS > vol 22 n° 3 (march 2008) . - pp 337 - 360[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-08021 RAB Revue Centre de documentation En réserve L003 Disponible 079-08022 RAB Revue Centre de documentation En réserve L003 Disponible In-flight geometric calibration of different cameras of IRS-P6 using a physical sensor model / P. Radhadevi in Photogrammetric record, vol 23 n° 121 (March - May 2008)PermalinkIntroduction au traitement d'images / D. Lingrand (2008)PermalinkSupporting the process of exploring and interpreting space-time multivariate patterns: the visual inquiry toolkit / J. Chen in Cartography and Geographic Information Science, vol 35 n° 1 (January 2008)PermalinkEGC'07, 7èmes journées francophones Extraction et gestion des connaissances, 23 - 26 janvier 2007, Namur, Belgique / Jérôme Euzenat (2007)PermalinkGéométrie discrète et images numériques / D. Coeurjolly (2007)PermalinkMathématiques pour la modélisation géométrique, la représentation 3D et la synthèse d'images / L. Garnier (2007)PermalinkMatching topographic surfaces : application to lidar and photogrammetric surfaces / Frédéric Bretar in Revue Française de Photogrammétrie et de Télédétection, n° 182 (Juin 2006)PermalinkUsing angular and spectral shape similarity constraints to improve MISR aerosol and surface retrievals over land / D. Diner in Remote sensing of environment, vol 94 n° 2 (30/01/2005)PermalinkAlgèbre linéaire et géométrie / Luc Jolivet (2005)PermalinkSolving algebraic computational problems in geodesy and geoinformatics / Joseph L. Awange (2005)PermalinkThe distance-similarity metaphor in network-display spatialisations / Sara Irina Fabrikant in Cartography and Geographic Information Science, vol 31 n° 4 (October 2004)PermalinkScaling net primary production to a MODIS footprint in support of Earth observing system product validation / D. Turner in International Journal of Remote Sensing IJRS, vol 25 n° 10 (May 2004)PermalinkThe scale matcher: a procedure for assessing scale compatibility of spatial data and models / L.R. Lilburne in International journal of geographical information science IJGIS, vol 18 n° 3 (april - may 2004)PermalinkImage numérique couleur, de l'acquisition au traitement / Alain Trémeau (2004)PermalinkManual of photogrammetry, fifth edition / J. Chris Mcglone (2004)PermalinkEfficient flow computation on massive grid terrain datasets / L. Arge in Geoinformatica, vol 7 n° 4 (December 2003)PermalinkFuzzy set approach to assessing similarity of categorical maps / Alex Hagen-Zanker in International journal of geographical information science IJGIS, vol 17 n° 3 (may 2003)PermalinkScale and orientation-invariant scene similarity metrics for image queries / A. Stefanidis in International journal of geographical information science IJGIS, vol 16 n° 8 (december 2002)PermalinkCoordinate conversion in a GIS environment: case-study of user-defined coordinate conversion for regional detroit / Y. Arisoy in GIM international, vol 15 n° 10 (October 2001)PermalinkPermalink