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Impact of the quality of spatial 3D city models on sensor networks placement optimization / M. Argany in Geomatica, vol 66 n° 4 (December 2012)
[article]
Titre : Impact of the quality of spatial 3D city models on sensor networks placement optimization Type de document : Article/Communication Auteurs : M. Argany, Auteur ; Mir Abolfazl Mostafavi, Auteur ; V. Akbarzadeh, Auteur ; et al., Auteur Année de publication : 2012 Article en page(s) : pp 291 - 305 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] capteur terrestre
[Termes IGN] données localisées dynamiques
[Termes IGN] milieu urbain
[Termes IGN] modèle 3D de l'espace urbain
[Termes IGN] optimisation (mathématiques)
[Termes IGN] qualité des données
[Termes IGN] réseau de capteurs
[Termes IGN] surveillanceRésumé : (Auteur) Sensor networks are increasingly used for tracking, monitoring, and observing spatial dynamic phenomena in the real world (e.g. urban area). In order to ensure an efficient deployment of a sensor network, several optimization algorithms have been proposed in recent years. Most of these algorithms often rely on oversimplified sensor models. In addition, they do not consider information on the terrain topography, city models, and the presence of diverse obstacles in the sensing area (e.g. buildings, trees, poles). Only some of those optimization algorithms attempt to consider the terrain information in the optimization of a sensor network deployment. However, most of these algorithms consider that the spatial models used for this purpose are perfect representations of the reality and are not sensitive to the quality of the information. However, spatial models are simplified representations of a complex reality, and hence are inherently uncertain. In this paper we will investigate the impact of the spatial data quality on the optimization of a sensor network and its spatial coverage in an urban area. For this purpose, we will investigate specific implications of spatial data quality criteria for a 3D city model that will be used in sensor network optimization algorithms. Then, we will analyze the impact of some of those criteria on the estimation of sensor network coverage. Afterwards, a case study for sensor network deployment in an urban area will be presented. This case study will demonstrate the impact of 3D city models quality on the estimation of coverage using global and local optimization algorithms. Finally, the results obtained from this experimentation will be presented and discussed. Numéro de notice : A2012-657 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE/SOCIETE NUMERIQUE Nature : Article DOI : 10.5623/cig2012-055 En ligne : https://doi.org/10.5623/cig2012-055 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32103
in Geomatica > vol 66 n° 4 (December 2012) . - pp 291 - 305[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 035-2012041 SL Revue Centre de documentation Revues en salle Disponible Triangular factorization-based simplex algorithms for hyperspectral unmixing / W. Xia in IEEE Transactions on geoscience and remote sensing, vol 50 n° 11 Tome 1 (November 2012)
[article]
Titre : Triangular factorization-based simplex algorithms for hyperspectral unmixing Type de document : Article/Communication Auteurs : W. Xia, Auteur ; H. Pu, Auteur ; et al., Auteur Année de publication : 2012 Article en page(s) : pp 4420 - 4440 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] algorithme d'apprentissage
[Termes IGN] algorithme du simplexe
[Termes IGN] analyse des mélanges spectraux
[Termes IGN] factorisation
[Termes IGN] image hyperspectrale
[Termes IGN] programmation linéaireRésumé : (Auteur) In the linear unmixing of hyperspectral images, the observation pixels form a simplex whose vertices correspond to the endmembers, hence finding the endmembers is equivalent to extracting these vertices. A common technique for determining vertices is to analyze the simplex volume, but it usually has a high computational complexity, resulting from the exhaustive searching of volume in the large hyperspectral data. This problem limits the practicability and real-time application. In this paper, we utilize triangular factorization (TF) to calculate the volume, deducing a method named simplex volume analysis based on TF (SVATF). It requires just one comparison through the data to succeed in finding the global optimal solution for all the endmembers, thus improving the searching efficiency. Dimensionality reduction transformation is not necessary, which is another advantage of this method. Moreover, since TF is a broad conception including different methods, SVATF is a framework including various implementations. Based on TF, we also propose a fast learning algorithm named abundance quantification based on TF to estimate the abundances, which further saves the computation by utilizing the intermediate values involved in SVATF. The abundance estimation method can rectify possible errors in the given endmembers by utilizing two important constraints (abundance nonnegative constraint and abundance sum-to-one constraint) of the linear mixture model, so it is useful for the imagery without pure pixels. Experimental results on synthetic and real hyperspectral data demonstrate that the proposed methods can obtain accurate results with much lower computational complexity, with respect to other state-of-the-art methods. Numéro de notice : A2012-587 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2195185 Date de publication en ligne : 22/05/2012 En ligne : https://doi.org/10.1109/TGRS.2012.2195185 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32033
in IEEE Transactions on geoscience and remote sensing > vol 50 n° 11 Tome 1 (November 2012) . - pp 4420 - 4440[article]A supervised and fuzzy-based approach determine optimal multi-resolution image segmentation parameters / H. Tong in Photogrammetric Engineering & Remote Sensing, PERS, vol 78 n° 10 (October 2012)
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Titre : A supervised and fuzzy-based approach determine optimal multi-resolution image segmentation parameters Type de document : Article/Communication Auteurs : H. Tong, Auteur ; T. Maxwell, Auteur ; Y. Zhang, Auteur ; V. Dey, Auteur Année de publication : 2012 Article en page(s) : pp 1029 - 1044 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] classification dirigée
[Termes IGN] classification floue
[Termes IGN] classification hybride
[Termes IGN] classification orientée objet
[Termes IGN] eCognition
[Termes IGN] image optique
[Termes IGN] optimisation (mathématiques)
[Termes IGN] résolution multiple
[Termes IGN] segmentation d'imageRésumé : (Auteur) Image segmentation is important for object-based classification. One of the most advanced image segmentation techniques is multi-resolution segmentation implemented by eCognition®. Multi-resolution segmentation requires users to determine a set of proper segmentation parameters through a trial-and-error process. To achieve accurate segmentations of objects of different sizes, several sets of segmentation parameters are required: one for each level. However, the trial-and-error process is time consuming and operator dependent. To overcome these problems, this paper introduces a supervised and fuzzy-based approach to determine optimal segmentation parameters for eCognition®. This approach is referred to as the Fuzzy-based Segmentation Parameter optimizer (fbsp optimizer) in this paper. It is based on the idea of discrepancy evaluation to control the merging of sub-segments to reach a target segment. Experiments demonstrate that the approach improves the segmentation accuracy by more than 16 percent, reduces the operation time from two hours to one-half hour, and is operator independent. Numéro de notice : A2012-484 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.78.10.1029 En ligne : https://doi.org/10.14358/PERS.78.10.1029 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31930
in Photogrammetric Engineering & Remote Sensing, PERS > vol 78 n° 10 (October 2012) . - pp 1029 - 1044[article]Towards usability engineering for online editors of Volunteered Geographic Information: A perspective on learnability / Catherine E. Jones in Transactions in GIS, vol 16 n° 4 (August 2012)
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Titre : Towards usability engineering for online editors of Volunteered Geographic Information: A perspective on learnability Type de document : Article/Communication Auteurs : Catherine E. Jones, Auteur ; Patrick Weber, Auteur Année de publication : 2012 Article en page(s) : pp 523 - 544 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique web
[Termes IGN] apprentissage (cognition)
[Termes IGN] convivialité
[Termes IGN] données localisées des bénévoles
[Termes IGN] interface web
[Termes IGN] logiciel d'éditique web
[Termes IGN] OpenStreetMap
[Termes IGN] optimisation (mathématiques)
[Termes IGN] participation du publicRésumé : (Auteur) This article presents one of the first systematic usability investigations for a Volunteered Geographic Information (VGI) editor. This research is motivated by the fact that although VGI is now widely consumed, contribution rates are lagging considerably. Compared to traditional GIS interfaces, with complex interfaces resulting in high cognitive loads and barriers to participation, VGI tools and interfaces need to be easy to use and learn to encourage and facilitate contributions. This article develops a case study of OpenStreetMap, one of the most successful VGI projects, and its default editor, Potlatch2. Ten participants with no prior experience of VGI contribution, were instructed to contribute data to OSM in a structured exercise, while being monitored using an eye tracker and audio/video screen capture software. Each participant was asked to Think Aloud, i.e. describe what they were thinking and doing as they completed the tasks. The results highlight significant usability issues impacting learnability, especially from the perspective of a new contributor: hidden functionality, lack of user feedback between interactions and the inefficient and inconsistent placement of functionality and map controls. The facilitation of VGI contributions clearly depends on designing targeted interfaces, optimized to the needs of specific levels of contributors with defined goals and expectations. Numéro de notice : A2012-365 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/SOCIETE NUMERIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/j.1467-9671.2012.01319.x En ligne : https://doi.org/10.1111/j.1467-9671.2012.01319.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31811
in Transactions in GIS > vol 16 n° 4 (August 2012) . - pp 523 - 544[article]Geometric unmixing of large hyperspectral images: A barycentric coordinate approach / Paul Honeine in IEEE Transactions on geoscience and remote sensing, vol 50 n° 6 (June 2012)
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Titre : Geometric unmixing of large hyperspectral images: A barycentric coordinate approach Type de document : Article/Communication Auteurs : Paul Honeine, Auteur ; C. Richard, Auteur Année de publication : 2012 Article en page(s) : pp 2185 - 2195 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] algorithme du simplexe
[Termes IGN] analyse des mélanges spectraux
[Termes IGN] classification barycentrique
[Termes IGN] image hyperspectraleRésumé : (Auteur) In hyperspectral imaging, spectral unmixing is one of the most challenging and fundamental problems. It consists of breaking down the spectrum of a mixed pixel into a set of pure spectra, called endmembers, and their contributions, called abundances. Many endmember extraction techniques have been proposed in literature, based on either a statistical or a geometrical formulation. However, most, if not all, of these techniques for estimating abundances use a least-squares solution. In this paper, we show that abundances can be estimated using a geometric formulation. To this end, we express abundances with the barycentric coordinates in the simplex defined by endmembers. We propose to write them in terms of a ratio of volumes or a ratio of distances, which are quantities that are often computed to identify endmembers. This property allows us to easily incorporate abundance estimation within conventional endmember extraction techniques, without incurring additional computational complexity. We use this key property with various endmember extraction techniques, such as N-Findr, vertex component analysis, simplex growing algorithm, and iterated constrained endmembers. The relevance of the method is illustrated with experimental results on real hyperspectral images. Numéro de notice : A2012-263 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2188408 Date de publication en ligne : 14/11/2011 En ligne : https://doi.org/10.1109/TGRS.2012.2188408 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31709
in IEEE Transactions on geoscience and remote sensing > vol 50 n° 6 (June 2012) . - pp 2185 - 2195[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2012061 RAB Revue Centre de documentation En réserve L003 Disponible Estimating forest attribute parameters for small areas using nearest neighbors techniques / Ronald E. McRoberts in Forest ecology and management, vol 272 (mai 2012)PermalinkExtraction of building roof contours from LiDAR data using a Markov-random-field-based approach / E. Dos Santos Galvanin in IEEE Transactions on geoscience and remote sensing, vol 50 n° 3 (March 2012)PermalinkPermalinkPermalinkImproving the Wishart synthetic aperture radar image classifications through deterministic simulated annealing / F. Sanchez-Llado in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 6 (November 2011)PermalinkUsing snakes for the registration of topographic road database objects to ALS features / J. Göpfert in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 6 (November 2011)PermalinkOptimiser la performance de calcul pour la cartographie en temps réel avec un laser scanner aéroporté / Jan Skaloud in Géomatique suisse, vol 109 n° 6 (juin 2011)PermalinkApproche non supervisée par processus ponctuels marqués pour l'extraction d'objets à partir d'images aériennes et satellitaires / S. Ben Hadj in Revue Française de Photogrammétrie et de Télédétection, n° 194 (Mai 2011)PermalinkA new pan-sharpening method using multiobjective particle swarm optimization and the shiftable contourlet transform / J. Saeedi in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 3 (May - June 2011)PermalinkAggregation of LoD 1 building models as an optimization problem / R. Guercke in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 2 (March - April 2011)Permalink