SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 MECOSIG Adapted to the Design of Distributed GIS F. Pasquasy, F. Laplanche, J-C. Sainte & J-P. Donnay Unit of Geomatics, University of Liège, Belgium
2 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 MECOSIG A method devoted to GIS design and implementation [published in 1996] considering: GIS as an Information System (IS) where IS Organization (systemic approach) Organization as the core of the method The method has been progressively improved (last decade) Emergence of distributed GIS involved : reassessment of the methodology new concerns and tools (fitting the requirements of distributed environments) identified
3 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 MECOSIG - Design protocol Method covering the complete GIS’s lifecycle using specific tools at different abstraction levels Descriptive to Logical-Physical level... Design protocol is summarized into a monitoring matrix every cell relates to specific tools (formalisms, models, prototyping …) semantic concerns (metadata, documentation …) Main concerns are Organization, Data, Data flows, Processes MECOSIG suggested to go twice through the monitoring matrix analysis stage (not anymore taken into account because of redundancy with the descriptive level in conception step) conception step
4 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 MECOSIG - Monitoring Matrix
5 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Descriptive level Group of actors of the organization(s) must be identified Actors have their own: set of privileges specific use cases More often a specialization relationship exists between them
6 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Descriptive level Concerning processes (in particular crossed processes in distributed GIS), interactions between groups of actors and the System are identified in terms of: textual descriptions UML use cases Data are identified according to use cases Data are described in a catalogue and quality must be analysed Use of standards (ISO & 19115) is recommended Further agreements must be achieved in order to incorporate semantic rules in spatial data domain (interoperability requirements …)
7 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 MECOSIG - Monitoring Matrix
8 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Conceptual level UML class diagram used to design Data (original formalism proposed in MECOSIG - CONGOO is substituted) is internationally admitted as standard (System modelling) offers more than only one diagram design can combine serial of models to depict a context Specificity of spatial data in UML object’s geometry a lot of studies [e.g. COMOSIG Workshops ER2004, Bédard & al., 2004] dealt with stereotypes or tagged values allow to adapt UML topological relationships concept of topological matrix (originally from CONGOO) is added and adapted two kinds of topological matrix are available the traditional matrix and the strong one
9 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Conceptual level
10 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Conceptual level Every use case is extracted from the descriptive level and detailed using UML activity diagrams Sequence diagrams are used to conceptualize specific scenarios of activity diagrams
11 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 MECOSIG - Monitoring Matrix
12 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Organizational level Facing the implementation of a distributed infrastructure, important organisational constraints must be met missions of all actors should be assessed and possibly redefined new tasks are introduced in order to guarantee maintenance, permanent working and growth of the distributed System new data flows are generated and others have to be adapted data exchange must be performed easily and in a transparent way for all users access to metadata [ISO standards] - particularly metadata related to quality (data usability and appraisal of final results) some data / services access can be restricted or subject to authorization(s)
13 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Organizational level From these purposes coming up representative’s committees in charge of coordination tasks formalization can also be introduced to depict their tasks (UML use cases, activity & sequence diagrams, …)
14 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 MECOSIG - Monitoring Matrix
15 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Logical-Physical level Roles and tasks of all actors should be clearly specified key is to associate all actors in the new System which will be set up e.g.: sensitizing and training sessions to facilitate the understanding of the re-engineered system possible reallocation of human resources Constitution of the representative’s committees in charge of coordination tasks competent and representative of the various departments or organizations receiving the ability to act decisively Managerial economies and economies of scale could be achieved Acquisition of common reference data Globalisation of software licenses
16 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Logical-Physical level A technical study must be completed to guarantee the required degree of interoperability to identify precisely add-on hardware and software distributed system components systems for cross-relating items of information across multiple sources Modelling process is to design objects which must be deployed in a distributed System e.g. data storage structure (components and deployment UML diagrams) previous activity and sequence diagrams (conceptual level) are improved by adding objects dealing with data flows, procedures and processes according to GIS software, tools and DBMS specificities...
17 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Logical-Physical level
18 SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Adaptations - Logical-Physical level Whole of the logical-physical level is integrated into a evolutionary project pilot
SEBGIS 2005, Agia Napa, Cyprus, October 31 - November 4, 2005 Thank you… Q / A ?