The REWERSE Working Group I4 on “Reasoning-aware Querying” aims at developing a Web query and transformation language offering both access to Web data and reasoning capabilities.

Within REWERSE , the Working Group I4 is one of five working groups concerned primarily with the development, specification, and understanding of core technologies, in the case of I4 with the development of a reasoning-aware query and transformation language for the Web.

REWERSE is a a research Network of Excellence on “Reasoning on the Web” funded by the European Commission and Switzerland within the Sixth Framework Programme (FP6). It started on 1st March 2004 and will run for four years receiving more than 5 million Euro in funding for 27 European research and industry organizations from 14 European countries and about 100 computer science researchers and professionals.

The objective of REWERSE is to establish Europe as a leader in the area of reasoning languages for advanced Web systems and applications, often referred to as Semantic Web systems and applications. The term ”Semantic Web” refers to one of the major current endeavours worldwide in Information Technologies. Its goal may be briefly described as enriching the existing Web with meta-data and data processing (and meta-data processing) so as to provide Web-based systems with advanced (so-called intelligent) capabilities, in particular with context awareness and decision support strengthening a person-centred, everyday use of the Web. [Bry and Schwertel, AgentLink News 15, 2004]

Objective of the I4 Working Group

Develop a Web query and transformation languages offering both access to Web data and reasoning capabilities. [REWERSE Consortium Aggreement, Technical Annex]

Description of Work

Retrieving data on the (conventional as well as Semantic) Web calls for a database-like querying and for “transforming” (i.e. re-structuring) the collected data. For this, “Web query and transformation languages” inspired from database query languages give rise to an easier programming and software maintenance. Data transformation is a first essential aspect of Semantic Web applications such as context-aware Web systems. As reasoning is a second essential aspect of Semantic Web applications, a Web query and transformation language offering reasoning capabilities would considerably ease the implementation Semantic Web applications. The objective of the WG is to develop, implement, and test (on selected Semantic Web applications) such a (provisionally rule-based) language at a pre-standard level.

The workplan for the first 48 months (as detailed in the overview of the Deliverables) is based on five milestones, respectively at 6, 12, 18, 24 and after 48 months. Through all the workplan, progress reports from the WG are expected every six months. Such progress reports will be formally shared and reasoned upon with all the other WGs, and mutual feedback will be taken into consideration for the each subsequent 6 months cycle. Within each cycle, general coordination/feedback will happen through the normal Network of Excellence coordination channels.

Refinement at Month 12

In the first twelve months, the working group has developed the principles of a versatile query language, i.e., a query language

1. for accessing both Semantic and conventional Web data,
2. for delivering data in Semantic and conventional Web data, and
3. for reasoning about such data.

Such query languages have shown itself to be very convenient for developing practical applications. The first prototype language developed in I4 fulfills this characteristic.

Furthermore, it has been noticed, that a reconsideration/extension of termination in presence of recursion is essential for a Semantic Web query and reasoning language.