Biomedical Adaptive Educational Hypermedia System: a Theoretical Model for Adaptive Navigation Support

The first Adaptive Hypermedia System (AHS) was presented in the early nineties (Furuta & Scotts, 1990), (Ginderen, 1990). However, this model was not based in World Wide Web (WWW). The first use in WWW appeared in 1996 (Brusilovsky, 1996). Currently, AHS are used for information recovery; interface adaptation, user assistance, learning support, dialogue, cooperation support and others applications. The AHS have become an alternative to traditional static hypermedia systems with the incorporation of dynamics in Web applications that need to adapt according users. Brusilovsky (1996) defines an AHS as hypertext and hypermedia system that reflect some user characteristic in a model and can adapt several visible aspects to the system for final user. In other words, the system should satisfy three main criteria: it should be hypertext or hypermedia, it should have an user model and it should be able to adapt using the user model. Brad Campbell and Joseph Goodman (1987) developed a model known as Hypertext Abstract Machine (HAM). The Dexter Hypertext Reference Model was originated from NIST Hypertext Standardization Workshop (Halasz & Schwartz, 1994). These models served as a formal reference and informal to the abstractions found in a wide range of hypertexts systems. The Trellis Model, developed by Stotts and Furuta (1990) was based on three elements: information content, navigation structures and application dynamics control. In 1992, the Tower Model was presented in the Workshop of National Institute of Standard and Technology. It was an object-oriented model, based on HAM model (Campbell & Goodman, 1987). The Amsterdam Hypermedia Model (AHM) developed by Hardman (1994) was based on Dexter Model. This model introduced the concept of time necessary to the complex relationships in hypermedia modelling. The AHM Model included temporal and space relationships among the elements and paid attention in behavior definition of links among the dynamic media groups. The work of Pagano (1992) presented a theoretical definition of hypertext. This model was extended by Almeida (Almeida, 2002) for educational hypermedia applications. The hypertexts and hypermedia systems that were mentioned previously are not adaptive. One the first efforts towards to put adaptivity of hypertexts / hypermedia systems was due to Benyon (1993) that proposed a model of AHS with modules composed User Model, Domain