This volume constitutes the refereed proceedings of the Fourth International Conference on Conceptual Structures, ICCS '96, held in Sydney, Australia, in August 1996. The book presents five full papers by the invited speakers together with 15 revised full papers selected for presentation at the conference from a respectable number of submissions. The issues addressed are natural language processing, information retrieval, graph operations, conceptual graph and Peirce theory, knowledge acquisition, theorem proving and CG programming, and order-based organisation and encoding.

This book constitutes the refereed proceedings of the Fifth International Conference on Conceptual Structures, ICCS '97, held in Seattle, Washington, USA, in August 1997. The 39 full papers presented were carefully selected and revised for inclusion in the volume. Also included are 9 abstracts of conceptual graphs tools. The papers are organized in sections on knowledge representation, knowledge modeling, formal concept analysis, formal reasoning, applications of conceptual graphs, and conceptual graphs tools. This book competently documents the progress achieved in the area since the predecessor conference ICCS '96, the proceedings of which have been published as LNAI 1115.

Computerscientistscreatemodelsofaperceivedreality.ThroughAItechniques, these models aim at providing the basic support for emulating cognitive - havior such as reasoning and learning, which is one of the main goals of the AI research e?ort. Such computer models are formed through the interaction of various acquisition and inference mechanisms: perception, concept learning, conceptual clustering, hypothesis testing, probabilistic inference, etc., and are represented using di?erent paradigms tightly linked to the processes that use them. Among these paradigms let us cite: biological models (neural nets, genetic programming), logic-based models (?rst-order logic, modal logic, rule-based s- tems), virtual reality models (object systems, agent systems), probabilistic m- els(Bayesiannets,fuzzylogic),linguisticmodels(conceptualdependencygraphs, language-based representations), etc. OneofthestrengthsoftheConceptualGraph(CG)theoryisitsversatilityin terms of the representation paradigms under which it falls. It can be viewed and therefore used, under di?erent representation paradigms, which makes it a p- ular choice for a wealth of applications. Its full coupling with di?erent cognitive processes lead to the opening of the ?eld toward related research communities such as the Description Logic, Formal Concept Analysis, and Computational Linguistic communities. We now see more and more research results from one community enrich the other, laying the foundations of common philosophical grounds from which a successful synergy can emerge.

With all of the news about the Internet and the Y2K problem, it is easy to forget that other areas of computer science still exist. Reading the newspaper or watching the television conveys a very warped view of what is happening in computer science. This conference illustrates how a maturing subdiscipline of computer science can continue to grow and integrate within it both old and new approaches despite (or perhaps due to) a lack of public awareness. The conceptual graph community has basically existed since the 1984 publication of John Sowa's book, "Conceptual Structures: Information Processing In Mind and Machine." In this book, John Sowa laid the foundations for a knowledge representation model called conceptual graphs based on semantic networks and the existential graphs of C.S. Peirce. Conceptual graphs constitutes a very powerful and expressive knowledge representation scheme, inheriting the benefits of logic and the mathematics of graphs. The expressiveness and formal underpinnings of conceptual graph theory have attracted a large international community of researchers and scholars. The International Conferences on Conceptual Structures, and this is the seventh in the series, is the primary forum for these researchers to report their progress and activities. As in the past, the doors were open to admit alternate representation models and approaches.

The book constitutes the refereed proceedings of the 11th International Conference on Conceptual Structures, ICCS 2003, held in Dresden, Germany in July 2003. The 23 revised full papers presented together with 5 invited papers were carefully reviewed and selected for presentation. The papers are organized in topical sections on the many facets of conceptual structures, logical and linguistic aspects, conceptual representation of time and space, deepening the formal theory and applications of conceptual structures.

This book constitutes the refereed proceedings of the 6th International Conference on Conceptual Structures, ICCS'98, held in Montpellier, France, in August 1998. The 20 revised full papers and 10 research reports presented were carefully selected from a total of 66 submissions; also included are three invited contributions. The volume is divided in topical sections on knowledge representation and knowledge engineering, tools, conceptual graphs and other models, relationships with logics, algorithms and complexity, natural language processing, and applications.