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Using landscape characteristics to define an adjusted distance metric for improving kriging interpolations / S. Lyon in International journal of geographical information science IJGIS, vol 24 n° 5-6 (may 2010)
[article]
Titre : Using landscape characteristics to define an adjusted distance metric for improving kriging interpolations Type de document : Article/Communication Auteurs : S. Lyon, Auteur ; R. Sorensen, Auteur ; J. Stendahl, Auteur ; J. Seibert, Auteur Année de publication : 2010 Article en page(s) : pp 723 - 740 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] azote
[Termes IGN] carbone
[Termes IGN] distance euclidienne
[Termes IGN] humidité du sol
[Termes IGN] interpolation
[Termes IGN] krigeage
[Termes IGN] métrique
[Termes IGN] Suède
[Termes IGN] variogrammeRésumé : (Auteur) Interpolation of point measurements using geostatistical techniques such as kriging can be used to estimate values at non-sampled locations in space. Traditional geostatistics are based on the spatial autocorrelation concept that nearby things are more related than distant things. In this study, additional information was used to modify the traditional Euclidean concept of distance into an adjusted distance metric that incorporates similarity in terms of quantifiable landscape characteristics such as topography or land use. This new approach was tested by interpolating soil moisture content, pH and carbon-to-nitrogen (C:N) ratio measured in both the mineral and the organic soil layers at a field site in central Sweden. Semivariograms were created using both the traditional distance metrics and the proposed adjusted distance metrics to carry out ordinary kriging (OK) interpolations between sampling points. In addition, kriging with external drift (KED) was used to interpolate soil properties to evaluate the ability of the adjusted distance metric to incorporate secondary data into interpolations. The new adjusted distance metric typically lowered the nugget associated with the semivariogram, thereby better representing small-scale variability in the measured data compared to semivariograms based on the traditional distance metric. The pattern of the resulting kriging interpolations using KED and OK based on the adjusted distance metric were similar because they represented secondary data and, thus, enhanced small-scale variability compared to traditional distance OK. This created interpolations that agreed better with what is expected for the real-world spatial variation of the measured properties. Based on cross-validation error, OK interpolations using the adjusted distance metric better fit observed data than either OK interpolations using traditional distance or KED. Copyright Taylor & Francis Numéro de notice : A2010-168 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Article DOI : 10.1080/13658810903062487 En ligne : https://doi.org/10.1080/13658810903062487 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30363
in International journal of geographical information science IJGIS > vol 24 n° 5-6 (may 2010) . - pp 723 - 740[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2010032 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010031 RAB Revue Centre de documentation En réserve L003 Disponible Spatial interpolation in wireless sensor networks: localized algorithms for variogram modeling and kriging / M. Umer in Geoinformatica, vol 14 n° 1 (January 2010)
[article]
Titre : Spatial interpolation in wireless sensor networks: localized algorithms for variogram modeling and kriging Type de document : Article/Communication Auteurs : M. Umer, Auteur ; Lars Kulik, Auteur ; Egemen Tanin, Auteur Année de publication : 2010 Article en page(s) : pp 101 - 134 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] corrélation
[Termes IGN] interpolation spatiale
[Termes IGN] krigeage
[Termes IGN] lissage de données
[Termes IGN] traitement de données localisées
[Termes IGN] variogrammeRésumé : (Auteur) Wireless sensor networks (WSNs) are rapidly emerging as the prominent technology for monitoring physical phenomena. However, large scale WSNs are known to suffer from coverage holes, i.e., large regions of deployment area where no sensing coverage can be provided. Such holes are the result of hardware failures, extensive costs for redeployment or the hostility of deployment areas. Coverage holes can adversely affect the accurate representation of natural phenomena that are monitored by a WSN. In this work, we propose to exploit the spatial correlation of physical phenomena to make monitoring systems more resilient to coverage holes. We show that a phenomenon can be interpolated inside a coverage hole with a high level of accuracy from the available nodal data given a model of its spatial correlation. However, due to energy limitations of sensor nodes it is imperative to perform this interpolation in an energy efficient manner that minimizes communication among nodes. In this paper, we present highly energy efficient methods for spatial interpolation in WSNs. First, we build a correlation model of the phenomenon being monitored in a distributed manner. Then, a purely localized and distributed spatial interpolation scheme based on Kriging interpolates the phenomenon inside coverage holes. We test the cost and accuracy of our scheme with extensive simulations and show that it is significantly more energy efficient than global interpolations and remarkably more accurate than simple averaging. Numéro de notice : A2010-011 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-009-0078-3 Date de publication en ligne : 24/02/2009 En ligne : https://doi.org/10.1007/s10707-009-0078-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81113
in Geoinformatica > vol 14 n° 1 (January 2010) . - pp 101 - 134[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2010011 RAB Revue Centre de documentation En réserve L003 Disponible Unsing spatial continuity and discontinuity information to retrieve geographic entities / Z. Xie in Geocarto international, vol 24 n° 1 (February - March 2009)
[article]
Titre : Unsing spatial continuity and discontinuity information to retrieve geographic entities Type de document : Article/Communication Auteurs : Z. Xie, Auteur ; L. Bian, Auteur Année de publication : 2009 Article en page(s) : pp 3 - 23 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] détection de contours
[Termes IGN] discontinuité
[Termes IGN] objet géographique
[Termes IGN] photographie aérienne
[Termes IGN] photographie numérique
[Termes IGN] reconnaissance d'objets
[Termes IGN] variogrammeRésumé : (Auteur) This paper presents three methods for representing spatial properties of geographic entity types in order to retrieve digital aerial photographs that contain these types. The three methods are semivariogram, edge tracing and an integration of the two methods. The first two methods are used to represent spatial continuity and spatial discontinuity information, respectively, associated with geographic entities, while the integrated method is used to represent both properties. The three methods are used to retrieve seven land cover types; factories, shopping centres, highways, forest, farmland, grasses and residential areas. Results show that between the two independent methods, the semivariogram method generally produces higher retrieval precision and more consistency across the seven types than the edge tracing method. The integrated method considerably outperforms the two independent methods. Copyright Taylor & Francis Numéro de notice : A2009-021 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106040801995828 Date de publication en ligne : 27/07/2009 En ligne : https://doi.org/10.1080/10106040801995828 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29651
in Geocarto international > vol 24 n° 1 (February - March 2009) . - pp 3 - 23[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-09011 RAB Revue Centre de documentation En réserve L003 Disponible SRTM resample with short distance-low nugget kriging / C.H. Grohmann in International journal of geographical information science IJGIS, vol 22 n° 8-9 (august 2008)
[article]
Titre : SRTM resample with short distance-low nugget kriging Type de document : Article/Communication Auteurs : C.H. Grohmann, Auteur ; S.S. Steiner, Auteur Année de publication : 2008 Article en page(s) : pp 895 - 806 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] géostatistique
[Termes IGN] image radar moirée
[Termes IGN] image SRTM
[Termes IGN] interpolation
[Termes IGN] interpolation inversement proportionnelle à la distance
[Termes IGN] krigeage
[Termes IGN] MNS SRTM
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle numérique de terrain
[Termes IGN] radargrammétrie
[Termes IGN] rééchantillonnage
[Termes IGN] variogrammeRésumé : (Auteur) The shuttle radar topography mission (SRTM), was flow on the space shuttle Endeavour in February 2000, with the objective of acquiring a digital elevation model of all land between 60° north latitude and 56° south latitude, using interferometric synthetic aperture radar (InSAR) techniques. The SRTM data are distributed at horizontal resolution of 1 arc-second (?30 m) for areas within the USA and at 3 arc-second (?90 m) resolution for the rest of the world. A resolution of 90 m can be considered suitable for the small or medium-scale analysis, but it is too coarse for more detailed purposes. One alternative is to interpolate the SRTM data at a finer resolution; it will not increase the level of detail of the original digital elevation model (DEM), but it will lead to a surface where there is the coherence of angular properties (i.e. slope, aspect) between neighbouring pixels, which is an important characteristic when dealing with terrain analysis. This work intents to show how the proper adjustment of variogram and kriging parameters, namely the nugget effect and the maximum distance within which values are used in interpolation, can be set to achieve quality results on resampling SRTM data from 3” to 1”. We present for a test area in western USA, which includes different adjustment schemes (changes in nugget effect value and in the interpolation radius) and comparisons with the original 1” model of the area, with the national elevation dataset (NED) DEMs, and with other interpolation methods (splines and inverse distance weighted (IDW)). The basic concepts for using kriging to resample terrain data are: (i) working only with the immediate neighbourhood of the predicted point, due to the high spatial correlation of the topographic surface and omnidirectional behaviour of variogram in short distances; (ii) adding a very small random variation to the coordinates of the points prior to interpolation, to avoid punctual artifacts generated by predicted points with the same location than original data points and; (iii) using a small value of nugget effect, to avoid smoothing that can obliterate terrain features. Drainages derived from the surfaces interpolated by kriging and by splines have a good agreement with streams derived from the 1” NED, with correct identification of watersheds, even though a few differences occur in the positions of some rivers in flat areas. Although the 1” surfaces resampled by kriging and splines are very similar, we consider the results produced by kriging as superior, since the spline-interpolated surface still presented some noise and linear artifacts, which were removed by kriging. Copyright Taylor & Francis Numéro de notice : A2008-307 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 13658810701730152 En ligne : https://doi.org/10.1080/13658810701730152 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29300
in International journal of geographical information science IJGIS > vol 22 n° 8-9 (august 2008) . - pp 895 - 806[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-08051 RAB Revue Centre de documentation En réserve L003 Disponible 079-08052 RAB Revue Centre de documentation En réserve L003 Disponible Aide-mémoire de géostatistique linéaire / P. Chauvet (2008)
Titre : Aide-mémoire de géostatistique linéaire Type de document : Guide/Manuel Auteurs : P. Chauvet, Auteur Editeur : Paris : Presses de l'Ecole des Mines Année de publication : 2008 Collection : Les cours de l'École des mines Importance : 311 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-2-911762-94-9 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] erreur systématique
[Termes IGN] espérance mathématique
[Termes IGN] estimation statistique
[Termes IGN] fonction aléatoire
[Termes IGN] krigeage
[Termes IGN] variance
[Termes IGN] variogrammeRésumé : (Editeur) Dans le foisonnement des méthodes issues du concept de " variable régionalisée " élaboré par le Professeur Georges Matheron dès la fin des années 50, des notions essentielles apparaissent de façon récurrente, soit au niveau des techniques mathématiques invoquées, soit au niveau de la signification epistémologique des applications effectives. Quel sens donner à la modélisation des réserves naturelles par une fonction aléatoire et comment réaliser effectivement cette modélisation ? Comment caractériser numériquement une structure spatiale, comment effectuer une estimation, quel sens lui attribuer et quelle confiance lui accorder... ? Voilà quelques-unes des interrogations permanentes qui fondent la démarche géostatistique. Ce livre regroupe en un seul document ces éléments de base de la géostatistique, tels qu'ils ont été effectivement exposés lors de plusieurs écoles d'été. Il a été délibérément choisi de se borner aux questions méthodologiques : significations, conditions d'application et propriétés des modèles constituent la matière de cet ouvrage, limité par ailleurs à l'aspect linéaire de la géostatistique. Tout en veillant à proposer un document pouvant se suffire à lui-même, l'auteur a constamment cherché à rappeler les références aux textes fondateurs de la discipline, à l'intention du lecteur soucieux de compléter cette première approche. Note de contenu : Éléments de géostatistique linéaire.
Introduction.
Chapitre 1 - Des variables régionalisées aux fonctions aléatoires.
Chapitre 2 - Géostatistique transitive.
Chapitre 3 - Buts et moyens de la géostatistique linéaire (1).
Chapitre 4 - Stationnarité et ergodicité.
Chapitre 5 - Buts et moyens de la géostatistique linéaire (2).
Chapitre 6 - Estimations.
Chapitre 7 - Vers les modèles non stationnaires.
Chapitre 8 - Géostatistique intrinsèque.
Chapitre 9 - Introduction à la géostatistique multivariable.
AnnexesNuméro de notice : 20631 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Manuel de cours Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=46851 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 20631-01 23.60 Livre Centre de documentation Mathématiques Disponible Geostatistical solutions for super-resolution land cover mapping / A. Boucher in IEEE Transactions on geoscience and remote sensing, vol 46 n° 1 (January 2008)PermalinkComputation of random errors in digital terrain models / J. Bjorke in Geoinformatica, vol 11 n° 3 (September - November 2007)PermalinkIntegrating fine scale information in super-resolution land-cover mapping / A. Boucher in Photogrammetric Engineering & Remote Sensing, PERS, vol 73 n° 8 (August 2007)PermalinkA novel method for mapping land cover changes: Incorporating time and space with geostatistics / A. Boucher in IEEE Transactions on geoscience and remote sensing, vol 44 n° 11 Tome 2 (November 2006)PermalinkModel-based prediction error uncertainty estimation for K-NN method / H.J. Kim in Remote sensing of environment, vol 104 n° 3 (15/10/2006)PermalinkSuper-resolution land cover mapping with indicator geostatistics / A. Boucher in Remote sensing of environment, vol 104 n° 3 (15/10/2006)PermalinkResolution dependent errors in remote sensing of cultivated areas / M. Ozdogan in Remote sensing of environment, vol 103 n° 2 (30/07/2006)PermalinkQuantifying spatial heterogeneity at the landscape scale using variogram models / S. Garrigues in Remote sensing of environment, vol 103 n° 1 (15 July 2006)PermalinkUrban land-use classification using variogram-based analysis with an aerial photograph / S.S. Wu in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 7 (July 2006)PermalinkRelating SAR image texture to the biomass of regenerating tropical forests / T.M. Kuplich in International Journal of Remote Sensing IJRS, vol 26 n° 21 (November 2005)Permalink