Models and metamodels play a cornerstone role in Model-Driven Software Development. Although several notations have been proposed to specify them, the kind of formal and tool support they provide is quite limited. In this paper we explore the use of Maude as a formal notation for describing models and metamodels. Maude is an executable rewriting logic language specially well suited for the specification of object-oriented open and distributed systems. We show how Maude offers a simple, natural, and accurate way of specifying models and metamodels, and offers good tool support for reasoning about them. In particular, we show how some basic operations on models, such as model subtyping, type inference, and metric evaluation, can be easily specified and implemented in Maude, and made available in development environments such as Eclipse. 1

Abstract. Provability-based semantic interoperability (PBSI) is a kind of interoperability that transcends mere syntactic translation to allow for robust, meaningful information exchange across systems employing ontologies for which mappings or matchings may not exist, and which can be evaluated by provability-based (PB) queries. We introduce a system of translation graphs to formalize the relationships between diverse ontologies and knowledge representation and reasoning systems, and to automatically generate the translation axioms governing PB information exchange and inter-system reasoning. We demonstrate the use of translation graphs on a small number of simple systems to achieve interoperability. Key words: translation graphs, provability-based semantic interoperability 1 What is Semantic Interoperability? The proliferation of knowledge-rich systems has led to the creation of myriad intelligent systems possessing diverse reasoning capabilities. Unfortunately, cooperative efforts among these systems are hindered by lack of a common representation

This paper systematically applies tools and techniques from the area of algebraic specification theory to corresponding ontology structuring and design tasks. We employ the heterogeneous structuring mechanisms of the heterogeneous algebraic specification language HetCasl for defining an abstract notion of structured heterogeneous ontology. This approach enables the designer to split up a heterogeneous ontology into semantically meaningful parts and employ dedicated reasoning tools to them. In particular, we distinguish three fundamentally different kinds of combining heterogeneous ontologies: integration, connection, and refinement.

INTELLLIGENNCE COMMUNITY towards effecctive exxploitattion and inttegration of intelliggence resources

Abstract. We present a general framework for the design of formal ontologies, resting on two main principles: firstly, we endorse Rudolf Carnap’s principle of logical tolerance by giving central stage to the concept of logical heterogeneity, i.e. the use of a plurality of logical languages within one ontology design. Secondly, to structure and combine heterogeneous ontologies in a semantically well-founded way, we base our work on abstract model theory in the form of institutional semantics, as forcefully put forward by Joseph Goguen and Rod Burstall. The theoretical foundation in institution theory establishes a close link to algebraic specification theory. We explore this link by systematically applying tools and techniques from this area to corresponding ontology structuring and design tasks, in particular employ the structuring mechanisms of the heterogeneous algebraic specification language HetCasl for defining an abstract notion of structured heterogeneous ontology, leading to the idea of a hyperontology, a heterogeneous, distributed,