Slide 3 of 29
Just storing the data can be a problem. Simple sequences of snapshots (raster or vector) waste space with redundant information.
The key is to provide tools to manipulate the information, which requires not just operations, but concepts appropriate to reasoning about change. We need the operations and predicates but we need them to be based in a clean conceptual framework.
Theoretically the storage may or may not mirror the concepts, but the first wave of systems make a close connection between the two. How the data is to be represented takes into account both conceptual adequacy (for the tasks to be aided) and considerations of implementation efficiency. As time goes on, less efficient, more indirect and more powerful representations will become practical (will require more computing power in real-time).
Sophisticated representations can be thought of as providing a pre-processing step. These considerations are generic but are most applicable to temporal field data (rasters).
