Reusability and adaptability of interactive resources in Web-based educational systems

The production of interactive multimedia content is in most cases an expensive task in terms of time and cost. Hence, optimizing production by exploiting the reusability of interactive multimedia elements is mandatory. Reusability can be triggered by a combination of resuable multimedia components and the appropriate use of metadata to control the components as well as their combination. In this article, we discuss the reusability aspects of interactive multimedia content in web-based learning systems. In contrast to existing approaches, we extend a component-based architecture to build interactive multimedia visualization units with the use of metadata for reusability and customizability. In the three-tier model, the lowest layer of the paradigm corresponds to the programmer (code reusability). The user interface of an educational visualization is located at the top layer where the interaction with the end-user (student) takes place. The educator is located between the top and the bottom layers. This medium layer allows adapting interactive multimedia content according to the needs of the user, applying a predefined set of metadata. The teacher can both adjust the level of explanation and the level of interactivity of an animation, and influence the presentation and the results of the algorithms being illustrated (program reusability). After a theoretical overview, we explain our architecture by giving an example of an application.