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Chapter 13
Nikos Zotos
Patras University, Greece
Sofa Stamou
Patras University, Greece
Topical and Spatio-Temporal
Search over Distributed
Online Databases
ABSTRACT
In this chapter, the authors propose a novel framework for the support of multi-faceted searches over
distributed Web-accessible databases. Towards this goal, the authors introduce a method for analyzing
and processing a sample of the database contents in order to deduce the topical, the geographic, and
the temporal orientation of the entire database contents. To extract the database topics, the authors
apply techniques leveraged from the NLP community. To identify the database geographic footprints,
the authors frst rely on geographic ontologies in order to extract toponyms from the database content
samples and then employ geo-spatial similarity metrics to estimate the geographic coverage of the identi-
fed toponyms. Finally, to determine the time aspects associated with the database entities, the authors
extract temporal expressions from the entities’ contextual elements and utilize a time ontology against
which the temporal similarity between the identifed entities is estimated.
DOI: 10.4018/978-1-61692-868-1.ch013