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Modeling in forestry using mixture models fitted to grouped and ungrouped data / Eric K. Zenner in Forests, vol 12 n° 9 (September 2021)  

Public [article]  inForests > vol 12 n° 9 (September 2021) . - n° 1196 Titre : Modeling in forestry using mixture models fitted to grouped and ungrouped data Type de document : Article/Communication Auteurs : Eric K. Zenner, Auteur ; Mahdi Teimouri, Auteur Année de publication : 2021 Article en page(s) : n° 1196 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques [Termes IGN] algorithme espérance-maximisation [Termes IGN] complexité [Termes IGN] diamètre à hauteur de poitrine [Termes IGN] distribution de Weibull [Termes IGN] distribution, loi de [Termes IGN] dynamique de la végétation [Termes IGN] estimation par noyau [Termes IGN] méthode du maximum de vraisemblance (estimation) [Termes IGN] modélisation de la forêt [Termes IGN] structure d'un peuplement forestier Résumé : (auteur) The creation and maintenance of complex forest structures has become an important forestry objective. Complex forest structures, often expressed in multimodal shapes of tree size/diameter (DBH) distributions, are challenging to model. Mixture probability density functions of two- or three-component gamma, log-normal, and Weibull mixture models offer a solution and can additionally provide insights into forest dynamics. Model parameters can be efficiently estimated with the maximum likelihood (ML) approach using iterative methods such as the Newton-Raphson (NR) algorithm. However, the NR algorithm is sensitive to the choice of initial values and does not always converge. As an alternative, we explored the use of the iterative expectation-maximization (EM) algorithm for estimating parameters of the aforementioned mixture models because it always converges to ML estimators. Since forestry data frequently occur both in grouped (classified) and ungrouped (raw) forms, the EM algorithm was applied to explore the goodness-of-fit of the gamma, log-normal, and Weibull mixture distributions in three sample plots that exhibited irregular, multimodal, highly skewed, and heavy-tailed DBH distributions where some size classes were empty. The EM-based goodness-of-fit was further compared against a nonparametric kernel-based density estimation (NK) model and the recently popularized gamma-shaped mixture (GSM) models using the ungrouped data. In this example application, the EM algorithm provided well-fitting two- or three-component mixture models for all three model families. The number of components of the best-fitting models differed among the three sample plots (but not among model families) and the mixture models of the log-normal and gamma families provided a better fit than the Weibull distribution for grouped and ungrouped data. For ungrouped data, both log-normal and gamma mixture distributions outperformed the GSM model and, with the exception of the multimodal diameter distribution, also the NK model. The EM algorithm appears to be a promising tool for modeling complex forest structures. Numéro de notice : A2021-721 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.3390/f12091196 En ligne : https://doi.org/10.3390/f12091196 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98639 [article]

Spatio-temporal-spectral observation model for urban remote sensing / Zhenfeng Shao in Geo-spatial Information Science, vol 24 n° 3 (July 2021)  

Public [article]  inGeo-spatial Information Science > vol 24 n° 3 (July 2021) . - pp 372 - 386 Titre : Spatio-temporal-spectral observation model for urban remote sensing Type de document : Article/Communication Auteurs : Zhenfeng Shao, Auteur ; Wenfu Wu, Auteur ; Deren Li, Auteur Année de publication : 2021 Article en page(s) : pp 372 - 386 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] biomasse aérienne [Termes IGN] cartographie des risques [Termes IGN] complexité [Termes IGN] fusion d'images [Termes IGN] image satellite [Termes IGN] inondation [Termes IGN] modèle mathématique [Termes IGN] scène urbaine [Termes IGN] surface imperméable [Termes IGN] zone urbaine Mots-clés libres : spatio-temporal-spectral observation model Résumé : (auteur) Taking cities as objects being observed, urban remote sensing is an important branch of remote sensing. Given the complexity of the urban scenes, urban remote sensing observation requires data with a high temporal resolution, high spatial resolution, and high spectral resolution. To the best of our knowledge, however, no satellite owns all the above characteristics. Thus, it is necessary to coordinate data from existing remote sensing satellites to meet the needs of urban observation. In this study, we abstracted the urban remote sensing observation process and proposed an urban spatio-temporal-spectral observation model, filling the gap of no existing urban remote sensing framework. In this study, we present four applications to elaborate on the specific applications of the proposed model: 1) a spatio-temporal fusion model for synthesizing ideal data, 2) a spatio-spectral observation model for urban vegetation biomass estimation, 3) a temporal-spectral observation model for urban flood mapping, and 4) a spatio-temporal-spectral model for impervious surface extraction. We believe that the proposed model, although in a conceptual stage, can largely benefit urban observation by providing a new data fusion paradigm. Numéro de notice : A2021-722 Affiliation des auteurs : non IGN Thématique : IMAGERIE/URBANISME Nature : Article DOI : 10.1080/10095020.2020.1864232 Date de publication en ligne : 08/02/2021 En ligne : https://doi.org/10.1080/10095020.2020.1864232 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98642 [article]

The urban governance configuration: A conceptual framework for understanding complexity and enhancing transitions to greater sustainability in cities / Isa Baud in Geography compass, vol 15 n° 5 (May 2021)  

Public [article]  inGeography compass > vol 15 n° 5 (May 2021) Titre : The urban governance configuration: A conceptual framework for understanding complexity and enhancing transitions to greater sustainability in cities Type de document : Article/Communication Auteurs : Isa Baud, Auteur ; Shazade Jameson, Auteur ; Elisabeth Peyroux, Auteur ; Dianne Scott, Auteur Année de publication : 2021 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale [Termes IGN] aide à la décision [Termes IGN] cadre conceptuel [Termes IGN] complexité [Termes IGN] croissance urbaine [Termes IGN] responsabilité environnementale [Termes IGN] transition énergétique [Termes IGN] ville durable Résumé : (auteur) This article proposes a conceptual framework for analysing and comparing urban governance configurations and their dynamics in the context of sustainability transitions. Our contribution to the debates consists of drawing on a literature review to develop a conceptual framework with the dimensions necessary for understanding urban governance processes and their dynamics; an urban governance configuration framework. We argue that this framework allows us to combine important dimensions (discourses, actor networks, knowledge and material processes) shaping urban development decision-making and outcomes in their social, economic and environmental domains, in a complex world. The main advantages of this approach are: first, it enables the analysis how complex decision-making is combined in a particular time and space, generating decisions and outcomes based on a variety of knowledge; second, it allows a comparative analysis of governance configurations across different places within the same city and between cities; and third, provides lessons on how urban governance could shift to more inclusive, sustainable forms of urban development. Numéro de notice : A2021-726 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/URBANISME Nature : Article DOI : 10.1111/gec3.12562 Date de publication en ligne : 04/05/2021 En ligne : https://doi.org/10.1111/gec3.12562 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98648 [article]

Cluttering reduction for interactive navigation and visualization of historical Images / Evelyn Paiz-Reyes (2021)  

Public Titre : Cluttering reduction for interactive navigation and visualization of historical Images Type de document : Article/Communication Auteurs : Evelyn Paiz-Reyes , Auteur ; Mathieu Brédif , Auteur ; Sidonie Christophe , Auteur Editeur : International Cartographic Association ICA - Association cartographique internationale ACI Année de publication : 2021 Collection : Proceedings of the ICA num. 4 Projets : Alegoria / Gouet-Brunet, Valérie Conférence : ICC 2021, 30th ICA international cartographic conference 14/12/2021 18/12/2021 Florence Italie Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse géovisuelle [Termes IGN] complexité [Termes IGN] environnement géographique virtuel [Termes IGN] exploration d'images [Termes IGN] image ancienne [Termes IGN] rendu (géovisualisation) [Termes IGN] rendu réaliste [Termes IGN] scène 3D [Vedettes matières IGN] Géovisualisation Résumé : (auteur) Iconographic representations, such as historical photos of geographic spaces, are precious cultural heritage resources capable of describing a particular geographical area’s evolution over time. These photographic collections may vary in size, between hundreds and thousands of items. With the advent of the digital era, many of these documents have been digitized, spatialized, and are available online. Browsing through these digital image collections represents new challenges. This paper examines the topic of historical image exploration in a virtual environment enabling the co-visualization of historical photos into a contemporary 3D scene. We address the topic of user interaction considering the potential volume of the input data. Our methodology is based on design guidelines that rely on visual perception techniques to ease visual complexity and improve saliency on specific cues. The designs are additionally implemented following an image-based rendering approach and evaluated in a group of users. Overall, these propositions may be a notable addition to creating innovative ways to visualize and discover historical images in a virtual geographic environment. Numéro de notice : C2021-048 Affiliation des auteurs : UGE-LASTIG (2020- ) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.5194/ica-proc-4-81-2021 Date de publication en ligne : 03/12/2021 En ligne : https://doi.org/10.5194/ica-proc-4-81-2021 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99434

How validation through model exploration empowers theories of spatial complexity : example of urban systems / Juste Raimbault (2021) 

Public contenu dans European Colloquium on Theoretical and Quantitative Geography 2021, Manchester, 3-5 November 2021 / Nuno Pinto (2021)   Titre : How validation through model exploration empowers theories of spatial complexity : example of urban systems Type de document : Article/Communication Auteurs : Juste Raimbault, Auteur ; Denise Pumain, Auteur Editeur : Manchester [Royaume-Uni] : Manchester University Press Année de publication : 2021 Conférence : ECTQG 2021, 22nd European Colloquium on Theoretical and Quantitative Geography 03/11/2021 05/11/2021 Manchester Royaume-Uni Open Access Abstracts Importance : pp 103 - 105 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale [Termes IGN] complexité [Termes IGN] interaction spatiale [Termes IGN] modèle de simulation Numéro de notice : C2021-075 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Communication DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100062

Documents numériques

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Understanding governance dynamics: The governing system of spatial data infrastructures / Jaap-Willem Sjoukema in International Journal of Spatial Data Infrastructures Research, vol 15 (Year 2020)  

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Geographical Modeling : Cities and Territories, ch. 4. Incremental Territorial Modeling / Clémentine Cottineau (2019)  

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Parametric bootstrap estimators for hybrid inference in forest inventories / Mathieu Fortin in Forestry, an international journal of forest research, vol 91 n° 3 (July 2018)  

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Complexity reduction in choropleth map animations by autocorrelation weighted generalization of time-series data / Christoph Traun in Cartography and Geographic Information Science, Vol 45 n° 3 (May 2018)  

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Use of unsupervised classification for the determination of prevailing land use typology / Miha Konjar in Geodetski vestnik, vol 61 n° 4 (December 2017 - February 2018)  

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The Naïve Overfitting Index Selection (NOIS): A new method to optimize model complexity for hyperspectral data / Alby D. Rocha in ISPRS Journal of photogrammetry and remote sensing, vol 133 (November 2017)  

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Modeling Mediterranean forest structure using airborne laser scanning data / Francesca Bottalico in International journal of applied Earth observation and geoinformation, vol 57 (May 2017)  

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Clutter and map legibility in automated cartography : a research agenda / Guillaume Touya in Cartographica, vol 51 n° 4 (Winter 2016)    

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The decision task complexity and information acquisition strategies in GIS-MCDA / Mohammadreza Jelokhani-Niaraki in International journal of geographical information science IJGIS, vol 29 n° 2 (February 2015)  

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Abstracting geographic information in a data rich world, ch. 7. Process modelling, web services and geoprocessing / Nicolas Regnauld (2014)  

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