Descripteur
Termes IGN > mathématiques > statistique mathématique > lissage de données
lissage de donnéesVoir aussi |
Documents disponibles dans cette catégorie (70)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
A DEM generalization by minor valley branch detection and grid filling / Tinghua Ai in ISPRS Journal of photogrammetry and remote sensing, vol 65 n° 2 (March - April 2010)
[article]
Titre : A DEM generalization by minor valley branch detection and grid filling Type de document : Article/Communication Auteurs : Tinghua Ai, Auteur ; J. Li, Auteur Année de publication : 2010 Article en page(s) : pp 198 - 207 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] détection automatique
[Termes IGN] données multiéchelles
[Termes IGN] généralisation automatique de données
[Termes IGN] généralisation de MNT
[Termes IGN] lissage de données
[Termes IGN] modèle numérique de surface
[Termes IGN] représentation du relief
[Termes IGN] réseau hydrographique
[Termes IGN] valléeRésumé : (Auteur) As an important method of terrain representation, a DEM usually needs to be generalized at multiple resolutions in order to adapt to different applications. The preservation of main landscape features is an important constraint in DEM generalization. The traditional generalization method based on signal processing by resampling or low-pass filtering is just a data compression operation rather than the abstraction of real information. This study develops a structured analysis method to generalize DEM data through the identification of minor valleys and filling the corresponding depression positions. The generalization process has two steps: geographic decision and geometric operation. According to their hydrological significance, the unimportant valley branches are detected and their corresponding coverage is filled by raising the terrain to make the terrain surface smoother. In contrast to the conventional algorithms based on image processing, this method is able to retain the main geographical characteristics more effectively in terrain representation. Copyright ISPRS Numéro de notice : A2010-092 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2009.11.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2009.11.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30288
in ISPRS Journal of photogrammetry and remote sensing > vol 65 n° 2 (March - April 2010) . - pp 198 - 207[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-2010021 SL Revue Centre de documentation Revues en salle 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]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 057-2010011 RAB Revue Centre de documentation En réserve L003 Disponible Efficient multiresolution spatial predictions for large data arrays / Magnussen, Steen in Remote sensing of environment, vol 109 n° 4 (30 August 2007)
[article]
Titre : Efficient multiresolution spatial predictions for large data arrays Type de document : Article/Communication Auteurs : Magnussen, Steen, Auteur ; Erik Naesset, Auteur ; Michael A. Wulder, Auteur Année de publication : 2007 Article en page(s) : pp 451 - 463 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] erreur moyenne quadratique
[Termes IGN] image multi sources
[Termes IGN] interpolation
[Termes IGN] interpolation inversement proportionnelle à la distance
[Termes IGN] lissage de données
[Termes IGN] modèle numérique de terrain
[Termes IGN] résolution multiple
[Termes IGN] signal laserRésumé : (Auteur) Imputations of missing values and optimal smoothing with massive data arrays poses a computational challenge since ordinary kriging becomes infeasible. Imputation and smoothing with standard algorithms like inverse distance weighted nearest neighbour interpolation (IDW) and interpolation on triangulated irregular networks (TIN/IP) fail to incorporate the spatial structure and ignore information beyond the neighbourhood. Multiresolution spatial models (MRSM) or approximate kriging methods adapted to handling massive data sets can be expected to do better than IDW and TIN/IP in terms of mean square errors of prediction (MSEP). We illustrate a MRSM that is efficient, computationally fast, and easy to implement. In two forestry examples with imputation of LiDAR range values the MRSM achieved a lower MSEP than IDW, TIN/IP, and fixed ranked kriging. MRSM appear as especially attractive for the construction of a DTM from last return LiDAR pulses. A third example demonstrates MRSM for efficient smoothing. Numéro de notice : A2007-319 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2007.01.018 En ligne : https://doi.org/10.1016/j.rse.2007.01.018 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28682
in Remote sensing of environment > vol 109 n° 4 (30 August 2007) . - pp 451 - 463[article]Building boundary tracing and regularization from airborne lidar point clouds / A. Sampath in Photogrammetric Engineering & Remote Sensing, PERS, vol 73 n° 7 (July 2007)
[article]
Titre : Building boundary tracing and regularization from airborne lidar point clouds Type de document : Article/Communication Auteurs : A. Sampath, Auteur ; J. Shan, Auteur Année de publication : 2007 Article en page(s) : pp 805 - 812 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] correction géométrique
[Termes IGN] détection du bâti
[Termes IGN] données lidar
[Termes IGN] lasergrammétrie
[Termes IGN] lissage de données
[Termes IGN] Maryland (Etats-Unis)
[Termes IGN] reconstruction 3D du bâti
[Termes IGN] segmentation
[Termes IGN] semis de points
[Termes IGN] TorontoRésumé : (Auteur) Building boundary is necessary for the real estate industry, flood management, and homeland security applications. The extraction of building boundary is also a crucial and difficult step towards generating city models. This study presents an approach to the tracing and regularization of building boundary from raw lidar point clouds. The process consists of a sequence of four steps: separate building and non-building lidar points; segment lidar points that belong to the same building; trace building boundary points; and regularize the boundary. For separation, a slope based 1D bi-directional filter is used. The segmentation step is a region-growing approach. By modifying a convex hull formation algorithm, the building boundary points are traced and connected to form an approximate boundary. In the final step, all boundary points are included in a hierarchical least squares solution with perpendicularity constraints to determine a regularized rectilinear boundary. Our tests conclude that the uncertainty of regularized building boundary tends to be linearly proportional to the lidar point spacing. It is shown that the regularization precision is at 18 percent to 21 percent of the lidar point spacing, and the maximum offset of the determined building boundary from the original lidar points is about the same as the lidar point spacing. Limitation of lidar data resolution and errors in previous filtering processes may cause artefacts in the final regularized building boundary. This paper presents the mathematical and algorithmic formulations along with stepwise illustrations. Results from Baltimore city, Toronto city, and Purdue University campus are evaluated. Copyright ASPRS Numéro de notice : A2007-314 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.73.7.805 En ligne : http://dx.doi.org/10.14358/PERS.73.7.805 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28677
in Photogrammetric Engineering & Remote Sensing, PERS > vol 73 n° 7 (July 2007) . - pp 805 - 812[article]A multi-resolution approach for filtering LiDAR altimetry data / José L. Silvan-Cardenas in ISPRS Journal of photogrammetry and remote sensing, vol 61 n° 1 (October 2006)
[article]
Titre : A multi-resolution approach for filtering LiDAR altimetry data Type de document : Article/Communication Auteurs : José L. Silvan-Cardenas, Auteur ; L. Wang, Auteur Année de publication : 2006 Article en page(s) : pp 11 - 22 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] convolution (signal)
[Termes IGN] données altimétriques
[Termes IGN] données lidar
[Termes IGN] filtrage du signal
[Termes IGN] gradient de pente
[Termes IGN] lissage de données
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle numérique de terrainRésumé : (Auteur) Discrimination of above-ground objects from terrain has proven to be surprisingly difficult to automate in computers, especially for large areas of varied terrain characteristics. Several methods have been developed for filtering the LiDAR data, of which three approaches are more prevalent: linear prediction, slope based and morphological filtering. A common ground to all these approaches is that the range of scales at which feature variations exist tends to be smaller than the range of scales at which terrain variations exist. In this paper, a model-based approach is described in which multiscale gradient of the surface variation is computed and used to adaptively erode the gridded LiDAR data within a multi-resolution, analysis–synthesis framework, namely the multiscale Hermite transform (MHT). The method was tested over nineteen datasets, including urban and forest areas. An average coefficient of agreement was computed over all datasets and compared with that obtained from other methods. Results showed that the proposed method was within the top three among nine methods tested. Copyright ISPRS Numéro de notice : A2006-438 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2006.06.002 En ligne : https://doi.org/10.1016/j.isprsjprs.2006.06.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28162
in ISPRS Journal of photogrammetry and remote sensing > vol 61 n° 1 (October 2006) . - pp 11 - 22[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-06071 SL Revue Centre de documentation Revues en salle Disponible Deriving ground surface digital elevation models from Lidar data with geostatistics / C.D. Lloyd in International journal of geographical information science IJGIS, vol 20 n° 5 (may 2006)PermalinkConsideration of smoothing techniques for hyperspectral remote sensing / C. Vaiphasa in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 2 (April 2006)PermalinkUncertainty analysis for soil-terrain models / T.F.A. Bishop in International journal of geographical information science IJGIS, vol 20 n° 2 (february 2006)PermalinkAnalyse et traitement des images numériques / Philippe Destuynder (2006)PermalinkAutomatic reconstruction of industrial installations using point clouds and images / Tahir Rabbani Shah (2006)PermalinkPermalinkCritical point detection using the length ration (LR) for line generalization / Byron Nakos in Cartographica, vol 40 n° 3 (September 2005)PermalinkGWR, MAUP et lissage par potentiels / Laure Charleux in Revue internationale de géomatique, vol 15 n° 2 (juin – août 2005)PermalinkA subdivision algorithm for smooth 3D terrain models / Norbert Pfeifer in ISPRS Journal of photogrammetry and remote sensing, vol 59 n° 3 (May 2005)PermalinkA vector-GIS extension for generalization of binary polygon patterns / H. Millward in Cartographica, vol 39 n° 4 (December 2004)Permalink