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A fundamental issue of Ubiquitous computing concerns the coordination gaps separating devices, services, and humans. Numerous heterogeneous devices, various information services, and users have different intentions and are physically located in environments, how can we coordinate the services and devices to assist a particular user in receiving a particular service so as to maximize the user's satisfaction? We propose an agent-based coordination framework for ubiquitous computing to solve this human-centered service coordination issue. It is called location-mediated coordination. This paper explains some coordination gaps in ubiquitous computing. It describes a conceptual framework of the location-mediated agent coordination and its implementation, context-aware information assistant systems in museums. [ABSTRACT FROM AUTHOR]

This paper describes SOUPA (Standard Ontology for Ubiquitous and Pervasive Applications) and the use of this ontology in building the Context Broker Architecture (CoBrA). CoBrA is a new agent architecture for supporting pervasive context-aware systems in a smart space environment. The SOUPA ontology is expressed using the Web Ontology Language OWL and includes modular component vocabularies to represent intelligent agents with associated beliefs, desire, and intentions, time, space, events, user pro- files, actions, and policies for security and privacy. Central to CoBrA is an intelligent broker agent that exploits ontologies to support knowledge sharing, context reasoning, and user privacy protection. We also describe two prototype systems that we have developed to demonstrate the feasibility and the use of CoBrA. [ABSTRACT FROM AUTHOR]

This paper illustrates an approach to combining the benefits of a multi-agent system architecture with the use of industry-standard modelling techniques using the Unified Modeling Language (UML). Using a UML profile for ontology modelling, an ontology for travel booking services is presented and the automatic derivation of an object-oriented content language for this domain is described. This content language is then used to encode example messages for a simple travel booking scenario, and it is shown how this approach to agent messaging allows messages to be created and analysed using a convenient object-oriented application-specific application programmer interface. [ABSTRACT FROM AUTHOR]

The unstructured, heterogeneous and dynamic nature of the Web poses a new challenge to query-answering over multiple data sources. The so-called Semantic Web aims at providing more and semantically richer structures in terms of ontologies and meta-data. A problem that remains is the combined use of heterogeneous sources. In a dynamic environment, it is no longer realistic to assume that the involved data sources act as if they were a single (virtual) source, modelled as a global schema, as is done in classical data integration approaches. In this paper, we propose an alternative approach where we replace the role of a single virtual data source schema with a peer-to-peer approach relying on limited shared (or: overlapping) vocabularies between peers. Since overlaps between vocabularies of peers will be limited and the dynamic nature of the system prohibits the design of accurate mappings, query processing will have to be approximate. We provide a formal model for such approximate query processing based on limited shared vocabularies between peers, and we show how the quality of the approximation can be adjusted in a gradual manner. The result is a flexible architecture for query-processing in heterogenous and dynamic environments, based on a formal foundation. We present the approach and discuss it on the basis of a case study. [ABSTRACT FROM AUTHOR]

This paper addresses current approaches to the goal of semantic interoperability on the web and presents new research directions. We critically discuss the existing approaches, including RDF, SHOE, PROMPT and Chimaera, and identify the most effective elements of each. In our opinion, the ability of these primarily closed solutions to succeed on a global web scale is limited. In general, a unilateral solution to the problem on a global level seems unlikely in the foreseeable future. We review and contrast our own research experiments AReXS and CASA and suggest that as yet unaddressed issues should be considered, such as reconciling implicit ontologies and evolving ontologies and task-oriented analysis. We also consider the role of semantic interoperation in multi-agent systems and describe strategies for achieving this via the ROADMAP methodology, with emphasis on building and assuring knowledge models. [ABSTRACT FROM AUTHOR]

Abstract. In this paper we propose reducing the degree of human interpretation currently necessary to understand an interaction protocol by describing at an abstract level the required agent actions that must be ‘plugged into’ the protocol for it to be executed. In particular, this can be done by designing and publishing ontologies describing the input and output data that are processed during the protocol's execution together with the actions and decisions that the agents must perform. An agent (or agent developer) that has previously defined mappings between the internal agent code and the actions and decisions in an ontology would then be able to interpret any interaction protocol that is defined with reference to that ontology. The discussion is based on the use of Coloured Petri Nets to represent interaction protocols and the Unified Modeling Language (UML) for ontology modelling. An alternative approach using Agent UML (AUML) is also outlined. [ABSTRACT FROM AUTHOR]