An Agent System Reasoning about the Web and the User

The paper describes some innovations related to the ongoing work on the GSA prototype, an integrated information retrieval agent. In order to improve the original system effectiveness, we propose the GSA2 system, introducing a new internal architecture based on a message-passing framework and on an ontology description formalism (WOLF, Web ontology Framework). GSA2 is conceived in order to describe and easily perform reasoning on "facts about the web and the user". The most innovative aspect of the project is its customizable and flexible reasoning system, based on Answer Set Programming; it plays the role of the central decision making module, and allows the Agent to take proactive decisions. The introduction of a logic language allows one to describe, program and plan behaviors of the Agent easily and quickly, and to experiment with a large variety of Information Retrieval strategies. Both the System Architecture and WOLF are general and reusable, and the result constitutes a good example of real implementation of agents based on logics

Reasoning about the semantic web using answer set programming

Abstract. The paper discusses some innovative aspects related to the integration of a framework based on Answer Set Programming in an Information Retrieval Agent, namely, the Global Search Agent. In order to improve the original system effectiveness, the GSA2 system introduces a new internal architecture based on a message-passing framework and on an ontology description formalism (WOLF, Web OntoLogy Framework), conceived in order to describe and make reasoning on “facts about the web and the user”. The role of a central intelligence is played by a reasoning system based on Answer Set Programming; it makes the Agent able to take independent decisions. The high expressive power of Answer Set Programming allows to describe, program and plan behaviors of the Agent easily and quickly, and to experiment with any (even future) Information Retrieval strategy. Both the System Architecture and WOLF are very general and reusable, and constitute a very good and interesting example of actual exploiting of Answer Set Programming for real applications.

The INFOMIX system for advanced integration of incomplete and inconsistent data

[No abstract available

Data integration: a challenging ASP application

The paper presents INFOMIX a successful application of ASP technology to the domain of Data Integration. INFOMIX is a novel system which supports powerful information integration, utilizing the ASP system DLV. While INFOMIX is based on solid theoretical foundations, it is a user-friendly system, endowed with graphical user interfaces for the average database user and administrator, respectively. The main features of the INFOMIX system are: (i) a comprehensive information model, through which the knowledge about the integration domain can be declaratively specified, (ii) capability of dealing with data that may result incomplete and/or inconsistent with respect to global constraints, (iii) advanced information integration algorithms, which reduce (in a sound and complete way) query answering to cautious reasoning on disjunctive Datalog programs, (iv) sophisticated optimization techniques guaranteeing the effectiveness of query evaluation in INFOMIX, (v) a rich data acquisition and transformation framework for accessing heterogeneous data in many formats including relational, XML, and HTML data. © Springer-Verlag Berlin Heidelberg 2005

Data Integration: a Challenging ASP Application

The paper presents INFOMIX a successful application of ASP technology to the domain of Data Integration. INFOMIX is a novel system which supports powerful information integration, utilizing the ASP system DLV. While INFOMIX is based on solid theoretical foundations, it is a user-friendly system, endowed with graphical user interfaces for the average database user and administrator, respectively. The main features of the INFOMIX system are: (i) a comprehensive information model, through which the knowledge about the integration domain can be declaratively specified, (ii) capability of dealing with data that may result incomplete and/or inconsistent with respect to global constraints, (iii) advanced information integration algorithms, which reduce (in a sound and complete way) query answering to cautious reasoning on disjunctive Datalog programs, (iv) sophisticated optimization techniques guaranteeing the effectiveness of query evaluation in INFOMIX, (v) a rich data acquisition and transformation framework for accessing heterogeneous data in many formats including relational, XML, and HTML data. © Springer-Verlag Berlin Heidelberg 2005