JAIST先端レクチャー・シリーズ（第6回）の開 催について

来る3月13日（火）に，下記の講演会を開催します。 ホットなトピックスに ついての分かりやすい講演ですので，多数の皆様（特に学生の方）に参加 いただきたく，ご案内申し上げます。

記

１．日　　時　平成24年3月13日 （火）15:00〜17:00

２．場　　所　JAIST　知識科学研究科　中講義室

３．講演題目　“Ontology-Based Data Access and Constraint 　　　　　　　　　Satisfaction” http://www.jaist.ac.jp/rcis/seminar/advanced/6

４．講 演 者　Frank Wolter 客員教授 　　　　　　　（リヴァプール大学　教授）

５．担当教員　小野寛晰 JAIST 先端融合領域研究院: http://www.jaist.ac.jp/rcis/l ogic-activities

------------------------------------------------------------------------- We would like to inform you of the JAIST Advanced Lecture Series 6 by a guest professor of JAIST as follows.

DATE：March 13, 2012 15:00-17:00 PLACE：JAIST KS Lecture Hall TITLE：“Ontology-Based Data Access and Constraint Satisfaction” SPEAKER：Prof. Frank Wolter (Univ. of Liverpool, Guest Professor of JAIST)

ABSTRACT： In recent years, the use of ontologies to access instance data has become increasingly popular. The general idea is that an ontology provides a vocabulary or conceptual model for the application domain, which can then be used as an interface for querying instance data and to derive additional facts. In this presentation, I will first introduce ontology-based data access (OBDA). I will focus on ontologies given in description logics or, equivalently, the web ontology language OWL. I will then establish a very close link between OBDA and constraint satisfaction problems with finite templates (CSP). Rather surprisingly, for the basic description logic ALC (=modal logic) OBDA and CSP turn out to be essentially equivalent. This result has a large number of consequences for ALC and OBDA in general.  I will focus on the following non-uniform complexity problem: what is the complexity of query answering for a fixed ontology? I will present general conditions under which this problem is in PTime and, respectively, coNP-hard. Using the CSP connection is shown that for ALC there is a P/coNP dichotomy for conjunctive query answering if, and only if, the famous, and still open, Feder/Vardi dichotomy conjecture for CSP holds.  The talk is based on joint work with Carsten Lutz.