A service context model based on ontology for content adaptation in E-learning

In heterogeneous service environment, E-learning, especially for learning content service, poses many opportunities and challengers of which the focus is that the service is even not able to be provided if the content can not be consumed in the service environment, termed service context also, which consists of the current state of networks, terminals, users, natural circumstance etc. To face the music, ISO/IEC proposes new standard, MPEG-21, in which content adaptation technology is employed to solve the problem of mismatch between content and service context. In content adaptation technology, service context model is a key point because it is the premise of other operations. Though service context modeling has been studied extensively recently and some models are created even standardized, there are some problems left still. One is that most of models are lack of ability of inference or the ability is weak because they are based on extensive makeup language (XML) or resource description framework (RDF). The other is that they are not capable of describing rules. However, it is necessary for service context model to reason and rule coding because those abilities will be helpful for datasize deceasing, context mining and subsequent processing, e.g. adaptation decision-taking, In this paper, we propose a novel model in the basis of ontology, whose property is to reason and describe rules. By ontology modeling software, protégé, the model is performed. Based on the result of implementation, it is proven that the model is feasible.