Many Multi-Agent Systems (MASs) have been built that represent different social structures, such as alliances, teams, coalitions, conventions and markets. Our primary objective in this work was to establish a fairly general-purpose market structure that can be reused in other market-based MASs. We have implemented different models of a deregulated electricity market. The models vary in the types of interaction between buyers and sellers, the mechanisms used to transact deals in the market, and in the role of the central agent. Extensive experiments were then conducted on the models to determine the type of market structure best suited for trading. The criteria of evaluation were based on resource consumption, number of deals completed, demand satisfied, supply used, excess-over-need bought, and prices paid. The conclusions should be applicable to other deregulated consumer markets of "perishable" commodities with strong time-dependence.

This paper describes the process of constructing a markup language for maritime information from the starting point of ontology building. Ontology construction from source materials in the maritime information domain is outlined. The structure of the markup language is described in terms of XML schemas and DTDs. A prototype application that uses the markup language is also described.