pax

Many database applications deal with spatio-temporal phenomena, and during the last decade a lot of research targeted location-based services, moving objects, traffic jam preventions, meteorology, etc. In strong contrast, there exist only very few proposals for an implementation of a spatio-temporal database system let alone a web-based spatio-temporal information system. This paper describes the design and implementation of a web-based spatio-temporal information system. The system uses Secondo as spatio-temporal DBMS for handling moving objects and MapServer as an OGC-compliant rendering engine for static spatial data. We describe the architecture of the system and compare our system with a standalone application. The paper investigates in detail issues that arise in the context of the web. First, we describe an implementation of a lightweight client that takes advantage of the functionality offered by Secondo and MapServer. Second, we describe how moving objects can be represented in GML. We discuss possible GML representations, propose an extension of GML that uses 3D segments (2D location + time) to represent moving objects, and present experiments that compare the solutions.

A web-enabled extension of a spatio-temporal DBMS

A web-enabled extension of a spatio-temporal DBMS

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