In the last decades information modelling and knowledge bases have become essentially important subjects not only in academic communities related to information systems and computer science but also in the business area where information technology is applied.

The 18th European-Japanese Conference on Information Modelling and Knowledge Bases (EJC 2008) continues the series of events that originally started as a cooperation initiative between Japan and Finland, already in the last half of the 1980's. Later (1991) the geographical scope of these conferences expanded to cover the whole Europe and other countries as well.

The EJC conferences constitute a world-wide research forum for the exchange of scientific results and experiences achieved in computer science and other related disciplines using innovative methods and progressive approaches. In this way a platform has been established drawing together researches as well as practitioners dealing with information modelling and knowledge bases. The main topics of EJC conferences target the variety of themes in the domain of information modelling, conceptual analysis, multimedia knowledge bases, design and specification of information systems, multimedia information modelling, multimedia systems, ontology, software engineering, knowledge and process management. We also aim at applying new progressive theories. To this end much attention is paid also to theoretical disciplines including cognitive science, artificial intelligence, logic, linguistics and analytical philosophy.

In order to achieve EJC targets, an international program committee selected 17 full papers, 6 short papers, 7 position papers in a rigorous reviewing process from 37 submissions. The selected papers cover many areas of information modelling, namely theory of concepts, database semantics, knowledge representation, software engineering, WWW information management, multimedia information retrieval, ontological technology, image databases, temporal and spatial databases, document data management, process management, and many others.

The conference could not be a success without the effort of many people and organizations.

In the Program Committee, 31 reputable researchers devoted a good deal of effort to the review process selecting the best papers and creating the EJC 2008 program. We are very grateful to them. Professor Yasushi Kiyoki, professor Takehiro Tokuda and professor Hannu Kangassalo were acting as co-chairs of the program committee. Dr. Naofumi Yoshida and his team in Program Coordination Team were managing the review process and the conference program. Professor Xing Chen was managing the conference venue and arrangement in the organizing committee. Professor Hannu Jaakkola acted as a general organizing chair and Ms. Ulla Nevanranta as a conference secretary for general organizational things necessary for annually running the conference series. We gratefully appreciate the efforts of all the supporters.

We believe that the conference will be productive and fruitful in the advance of research and application of information modelling and knowledge bases.

The Editors

Yasushi Kiyoki, Takahiro Tokuda, Hannu Jaakkola, Xing Chen, Naofumi Yoshida