  Recent years have witnessed a new trend of building ontology-based question
answering systems. These systems use semantic web information to produce more
precise answers to users' queries. However, these systems are mostly designed
for English. In this paper, we introduce an ontology-based question answering
system named KbQAS which, to the best of our knowledge, is the first one made
for Vietnamese. KbQAS employs our question analysis approach that
systematically constructs a knowledge base of grammar rules to convert each
input question into an intermediate representation element. KbQAS then takes
the intermediate representation element with respect to a target ontology and
applies concept-matching techniques to return an answer. On a wide range of
Vietnamese questions, experimental results show that the performance of KbQAS
is promising with accuracies of 84.1% and 82.4% for analyzing input questions
and retrieving output answers, respectively. Furthermore, our question analysis
approach can easily be applied to new domains and new languages, thus saving
time and human effort.
