Proposition de nouvelles fonctionnalités WikiSIG pour supporter le travail collaboratif en Geodesign

L’émergence du Web 2.0 se matérialise par de nouvelles technologies (API, Ajax…), de nouvelles pratiques (mashup, geotagging…) et de nouveaux outils (wiki, blog…). Il repose principalement sur le principe de participation et de collaboration. Dans cette dynamique, le Web à caractère spatial et cartographique c’est-à-dire, le Web géospatial (ou GéoWeb) connait lui aussi de fortes transformations technologiques et sociales. Le GéoWeb 2.0 participatif se matérialise en particulier par des mashups entre wikis et géobrowsers (ArgooMap, Geowiki, WikiMapia, etc.). Les nouvelles applications nées de ces mashups évoluent vers des formes plus interactives d’intelligence collective. Mais ces applications ne prennent pas en compte les spécificités du travail collaboratif, en particulier la gestion de traçabilité ou l’accès dynamique à l’historique des contributions. Le Geodesign est un nouveau domaine fruit de l’association des SIG et du design, permettant à une équipe multidisciplinaire de travailler ensemble. Compte tenu de son caractère émergent, le Geodesign n’est pas assez défini et il requiert une base théorique innovante, de nouveaux outils, supports, technologies et pratiques afin de s'adapter à ses exigences complexes. Nous proposons dans cette thèse de nouvelles fonctionnalités de type WikiSIG, bâties sur les principes et technologies du GéoWeb 2.0 et visant en particulier à supporter la dimension collaborative du processus de Geodesign. Le WikiSIG est doté de fonctionnalités wiki dédiées à la donnée géospatiale (y compris dans sa composante géométrique : forme et localisation) permettant d’assurer, de manière dynamique, la gestion documentée des versions des objets et l’accès à ces versions (et de leurs métadonnées), facilitant ainsi le travail collaboratif en Geodesign. Nous proposons également la deltification qui consiste en la capacité de comparer et d’afficher les différences entre deux versions de projets. Finalement la pertinence de quelques outils du géotraitement et « sketching » est évoquée. Les principales contributions de cette thèse sont d’une part d’identifier les besoins, les exigences et les contraintes du processus de Geodesign collaboratif, et d’autre part de proposer des nouvelles fonctionnalités WikiSIG répondant au mieux à la dimension collaborative du processus. Pour ce faire, un cadre théorique est dressé où nous avons identifié les exigences du travail collaboratif de Geodesign et proposé certaines fonctionnalités WikiSIG innovantes qui sont par la suite formalisés en diagrammes UML. Une maquette informatique est aussi développée de façon à mettre en oeuvre ces fonctionnalités, lesquelles sont illustrées à partir d’un cas d’étude simulé, traité comme preuve du concept. La pertinence de ces fonctionnalités développées proposées est finalement validée par des experts à travers un questionnaire et des entrevues. En résumé, nous montrons dans cette thèse l’importance de la gestion de la traçabilité et comment accéder dynamiquement à l’historique dans un processus de Geodesign. Nous proposons aussi d’autres fonctionnalités comme la deltification, le volet multimédia supportant l’argumentation, les paramètres qualifiant les données produites, et la prise de décision collective par consensus, etc.The emergence of Web 2.0 is materialized by new technologies (APIs, Ajax ...), by new practices (mashup, geotagging ...) and by new tools (wiki, blog ...). It is primarily based on the principle of participation and collaboration. In this dynamic, the web mapping with spatial character or simply called Geospatial Web (or Geoweb) evolves by strong technological and social changes. Participatory GeoWeb 2.0 is materialized in particular by mashups among wikis and géobrowsers (ArgooMap, Geowiki, WikiMapia, etc.). The new applications resulting from these mashups are moving towards more interactive forms of collective intelligence. However, these applications do not take into account the collaborative work or the traceability management or the dynamic access to the history of contributions. The Geodesign is a new area, which is the coupling between GIS and design, allowing a multidisciplinary team to work together. As it is an emergent term, the Geodesign has not be well defined and it requires innovative theoretical basis, new tools, media, technologies and practices to fit its complex requirements. We propose precisely in this thesis new features of WikiGIS, which is built on Web 2.0 technologies, and GeoWeb 2.0 aiming in particular to support the collaborative dimension of Geodesign process. The WikiGIS consists of wiki features for the geospatial data (including its geometric component: shape and location) to ensure, dynamically, the documented release management objects and access to these versions (and metadata), facilitating collaborative work on Geodesign. It aims to produce geographic information, while ensuring the quality and credibility of data created. We propose the “deltification” as one of the innovative features of WikiGIS, it is the ability to compare and display the differences between two versions of a project. Finally, the relevance of some geoprocessing and "sketching" tools is mentioned. The main contributions of the present thesis are firstly identifying the needs, requirements and constraints of collaborative Geodesign process, and secondly to offer new features of WikiSIG best meeting to the collaborative dimension of this process. For this, a theoretical framework is drawn up which we identified the requirements of the collaborative Geodesign process and we proposed some innovative features that are subsequently formalized by UML. A user mock-up is developed in order to show the WikiGIS features, which are illustrated on a simulated case study, treated as proof of concept. Finally, these concepts are ultimately validated by experts through a questionnaire and interviews. Briefly, we have amply demonstrated in this thesis the importance of traceability management and how to dynamically access in the historic of Geodesign process and we have proposed other features like deltification, multi-media component that supports the arguments, parameters describing the data produced, decision making by consensus, etc

Ground Reflectance Retrieval on Horizontal and Inclined Terrains Using the Software Package REFLECT

This paper presents the software package REFLECT for the retrieval of ground reflectance from high and very-high resolution multispectral satellite images. The computation of atmospheric parameters is based on the 6S (Second Simulation of the Satellite Signal in the Solar Spectrum) routines. Aerosol optical properties are calculated using the OPAC (Optical Properties of Aerosols and Clouds) model, while aerosol optical depth is estimated using the dark target method. A new approach is proposed for adjacency effect correction. Topographic effects were also taken into account, and a new model was developed for forest canopies. Validation has shown that ground reflectance estimation with REFLECT is performed with an accuracy of approximately ±0.01 in reflectance units (for the visible, near-infrared, and mid-infrared spectral bands), even for surfaces with varying topography. The validation of the software was performed through many tests. These tests involve the correction of the effects that are associated with sensor calibration, irradiance, and viewing conditions, atmospheric conditions (aerosol optical depth AOD and water vapour), adjacency, and topographic conditions

Towards a Conceptual Framework for WikiGIS

As an emerging complex concept, GeoDesign requires an innovative theoretical basis, tools, supports and practices. For this reason, we propose a new concept, “WikiGIS”, designed to answer some dimensions of the GeoDesign process. WikiGIS focuses on the needs of GeoDesign, but we leave the door open for future improvement when tested in other areas that may have additional needs. WikiGIS is built on Web 2.0 technologies—and primarily on wiki—to manage the tracking of participants’ editing (i.e., managing the contributions history). It also offers GIS functions for geoprocessing and a design-based approach for sketching proposals. One of the main strengths of WikiGIS is its ability to manage the traceability of contributions with an easy and dynamical access, data quality and deltification. The core of this paper consists of presenting a conceptual framework for WikiGIS using UML diagrams. A user interface is presented later to show how our WikiGIS proposal works. This interface is simply a means to illustrate the concepts underlying WikiGIS

WikiGIS Basic Concepts: Web 2.0 for Geospatial Collaboration

With the emergence of Web 2.0, new applications arise and evolve into more interactive forms of collective intelligence. These applications offer to both professionals and citizens an open and expanded access to geographic information. In this paper, we develop the conceptual foundations of a new technology solution called WikiGIS. WikiGIS’s strength lies in its ability to ensure the traceability of changes in spatial-temporal geographic components (geometric location and shape, graphics: iconography and descriptive) generated by users. The final use case highlights to what extent WikiGIS could be a relevant and useful technological innovation in Geocollaboration