collaborators

5 papers

cs.DB2008

Temporal Support of Regular Expressions in Sequential Pattern Mining

Leticia Gomez, Bart Kuijpers, Alejandro Vaisman

Classic algorithms for sequential pattern discovery, return all frequent sequences present in a database, but, in general, only a few ones are interesting for the user. Languages b…

cs.LO2008

A triangle-based logic for affine-invariant querying of spatial and spatio-temporal data

Sofie Haesevoets, Bart Kuijpers

In spatial databases, incompatibilities often arise due to different choices of origin or unit of measurement (e.g., centimeters versus inches). By representing and querying the da…

cs.LO2007

A case study of the difficulty of quantifier elimination in constraint databases: the alibi query in moving object databases

Bart Kuijpers, Walied Othman, Rafael Grimson

In the constraint database model, spatial and spatio-temporal data are stored by boolean combinations of polynomial equalities and inequalities over the real numbers. The relationa…

cs.DB20072 cited

Aggregation Languages for Moving Object and Places of Interest Data

Leticia Gomez, Bart Kuijpers, Alejandro Vaisman

We address aggregate queries over GIS data and moving object data, where non-spatial data are stored in a data warehouse. We propose a formal data model and query language to expre…

cs.DB20078 cited

Spatial Aggregation: Data Model and Implementation

Leticia Gomez, Sofie Haesevoets, Bart Kuijpers +1

Data aggregation in Geographic Information Systems (GIS) is only marginally present in commercial systems nowadays, mostly through ad-hoc solutions. In this paper, we first present…