GEO2DIS evaluation report

Bouvier B., Havas R., Hayot P., Della Maggiore R., Musone A., Mogorovich P., Riedhammer S., Rugani U., Trevisani M.

Products  Market  Dissemination  Geographical data server  Catalogue  Object oriented  Spatial index  Database Applications. Spatial databases and GIS 

The geographical data, both raster (satellite images, aerial photographs, scanned maps, ...) and vector (DCW, IGN products like BDTopo and BDCarto, ...) are growing up exponentially in amount, complexity and variety. Need of geographical data are growing in the same way among governmental and local autorithies and commercial and industrial operators for various applications like urban planning, environment monitoring, civil engineering project impact studies and communication networks design . Therefore, potential users have a ever increasing need of services provided by responsive organisations (data distributors) using efficient tools for acquiring geographical data, i.e. identifying, locating, selecting, purchasing and retrieving it. The ESPRIT III project n°8017 GEographical Object Oriented heterogeneous Data Information Server (GEO2DIS) was born out of this need for efficient tools for geographical data acquisition. It was entrusted to a Consortium whose partners are MATRA SYSTEMES & INFORMATION from France. DORNIER from Germany and INTECS from Italy, with associated partners : IGN, O2 Technology, CNUCE-CNR, Region Toscana and the municipality of Pisa. Project goals were the definition of consolidated user requirements at the European level, the definition of a common architecture of the geographical data server and the validation of the concept and of the architecture through three applications. The project has designed, implemented and validated a system based on two types of stations the data distributor station and the data user station, connected through LAN or WAN. The data user station allows users to submit queries to the catalogue and to define and issue a request for data and to receive them using powerful MMI, where the footprint of the data are located on a Reference Background. This MMI is customisable to the user's needs. The data distributor station answers to the requests of the data user station and offers the services of managing the catalogue and the data. managing the For the description of the heterogeneous geographical data sets a common data model has been defined as an object class. For GDS (and GDS descriptions) request, the Geographical Object Query Language (GeOQL, extension of the OQL (Object Query Language), which is part of the standard ODMG 93. This architecture allows to build the system on various GIS or DBMS, according to the operational requirements of the data distributor. It was actually implemented on the GIS Arc-Info and the OODBMS O2 which has been fitted with a spatial indexing module giving responses times divided by ten compared with previous tools. The system has been validated by three users using it for acquiring data for three very different applications : Assessment of the Visual Impact of a sport and leisure centre in Deulemont (France), monitoring of the land use, suitability analysis for an waste disposal site near Pisa. The innovation and benefits of the system are that, even now, no other tool than GEO2DIS offers all the features needed for acquiring geographical data : the capability to manage large amount of data of both vector (including 3D objects) and raster types and the geographical continuity, use by potential non IT specialists users, efficient response time and acquisition methods. As the needs of the users and the state of the technology continuously progress, some improvements have to be planned for the system. The most important of them is the use of Web clients. Partners are marketing the system. Multilingual commercial leaflet and technical description have been produced. Presentation have been made to potential customers.

Source: Project report, GEO2DIS, pp.1–121, 1997