J. Puustjärvi (Finland)
E-learning, Virtual universities, One-stop portals, Web services, Mediators
Today finding appropriate e-learning courses, or larger e learning objects, from different virtual universities is not easy task as they do not provide integrated access. How ever, providing integrated access is problematic as single e-learning systems are independently created, and hence do not follow or lack standardized metadata or ontology descriptions. In this paper, we present how such problems are solved in the ONES prototype system. A salient fea ture of the system is that it supports both traditional que ries (such as traditional database systems) and searches based on similarity match (i.e., learning object having the best match is presented first). These user-friendly features drove us to make some extensions to LOM. The architec ture of the system is based on a mediator and wrappers. The function of the wrappers is to hide the heterogeneity of e-learning systems. Their interface is implemented by web service technology, and so local e-learning systems are reusable, i.e., they may behave as a component in many global e-learning systems. This reusability feature also required us to develop a well-defined ontology for learning objects. Since OWL Web Ontology Language provides high expression power we used it in ontology specification. In addition OWL-specifications are used in solving the semantic heterogeneity of e-learning systems.
Important Links:
Go Back
