STRATIFIED HYPERMEDIA STRUCTURES FOR INFORMATION DISCLOSURE

In this paper we generalise the two-level approach to hypertext (hypermedia) systems into stratified hypermedia structures. First we describe the overall architecture of such systems, including the fundamentals of the user interface. Thereafter, its various components are discussed. Special emphasis is paid on how the underlying information model is layered. Two layers are featured: the hyperbase and the hyperindex. A characterisation calculus is presented for the characterisation of structured elements. This calculus forms the basis of a logic-based approach in connection with the associated information processor (Disclosure Machine). The logic-based approach is considered as the most general approach to the retrieval process. In addition, this calculus is useful for quality assurance in hypermedia applications. Attention is also paid to spatial coherence for relevance judgements.