RIA: Formalization, Inference, and Query Processing of Spatial Relations in Geographic Space

Interim Report, Year 2

For the second year of this 3-year grant, we planned two tasks in Integrated Spatial Reasoning. We have accomplished both tasks and advanced further than expected. Since we addressed already during the first year some of the tasks planned initially for the second year, we reformulated with last yearÕs progress report the goals for this year. The following tasks refer to this revised project plan. All completed tasks have been documented in papers, theses, and technical papers, some of which have been published already in refereed conferences or have been accepted in refereed journals. A complete list of publications is enclosed, as well as reprints of published journal papers acknowledging support from IRI-9309230. To date, a total of six refereed journal articles, seven refereed conference proceedings, five non-refereed conference papers, and one Ph.D. thesis have been published on Spatial Reasoning since the start of the grant in September 1993. We found that our results were extremely useful to address the assessment of consistency in geographic databases with multiple representations for the same spatial objects. Multiple-representation or multi-scale geographic databases keep "copies" of the same scene at different levels of detail. Representations of less detail are derived through (cartographic) generalization operations from the more-detailed operations. Consistency assessment is critical as, for instance, the National Spatial Data Infrastructure (NSDI) assumes that such generalizations can be obtained automatically; however, to date no comprehensive methods exist for automated quality control of such generalizations.

We also found that the 9-intersection, our model for topological relations, provides an excellent basis for the definition of the semantics of natural-language spatial predicates, such as "enters," "goes through," or "goes into." This may lead to much improved spatial query languages, incorporating concepts and terms close to the way humans think about spatial problems. During year 3, we plan to focus on extending our investigations in Integrated Spatial Reasoning with the following two tasks:

List of Publications

[ Project Summary | Spatial Database Research Group | NCGIA Maine ]