Date: Tue 18 Nov
Time: 15.00
Place: room 214

Speaker: Nectaria Tryfona, Department of Computer Science, Aalborg University, Denmark
Title: Designing Spatial Information Systems: Methodologies, Models and Tools
Reference: Michela Bertolotto

Abstract. Spatial Information Systems belong to the new, "non-standard" application areas with special data modeling and processing needs and extended demands on transaction management. In this work we extend models and tools, provided by standard application development methodologies used for "classical" applications, to serve the needs of geographic applications. In particular: (1) we propose a General Geographic Model for the definition of the basic concepts of geographic objects, geometric types, and elementary spatial operations and relationships; (2) we define the formal syntax and semantics of GeoIFO, which serves as a prototypical semantic model suitable for spatial database modeling at the conceptual level; (3) we propose the formal, yet practical, GeoRelational Data Model for the logical level, which provides a small set of representational constructs (relations and layers for the logical schema; virtual layers, object classes and spatial constraints for the user views) on top of well-established models and, (4) finally we present rules for transforming a GeoIFO schema to GeoRelational one which served as a basis for the Geographic Computer-Aided Software Engineering tool. Our proposal has been used to construct prototypical applications, small commercial systems, and large research projects. It has received a welcome acceptance by both users, who found it easy to understand, and developers, who adopted it quickly. The contribution of this work is the long-term productivity pay-offs of the methodology: although more time is spent for the analysis, design and even individual module coding, the overall system cost including integration, documentation and most importantly maintenance, is much lower and the achieve quality much higher.

Dr. Nectaria Tryfona is assistant professor in the Department of Mathematics and Computer Science at the University of Aalborg, Denmark. She received her Dipl. Eng. and Ph.D. from the Department of Computer Engineering and Informatics of the University of Patras (Greece) in 1991, and 1994, respectively. Upon graduation from the University of Patras she joined the National Center of Geographic Information and Analysis at the University of Maine in USA as Post Doctoral Research Associate and was involved in research projects aiming at the assessment of geographic information consistency at multiple levels of representation. Her expertise and current research interests and activities are focused in the area of Database Modeling, Geographic Information Systems Design and Spatio-Temporal Information Systems and Interoperability of Spatial Systems. Her major scientific interests focus on database design, non-standard and large-scale Information Systems, Computer Aided Software Engineering Tools, Heterogeneous Databases, Spatial Interoperability and Open Geographic Systems.