In order to achieve optimal efficiency in a learning process, individual learner needs his/her own personalized assistance. For a web-based open and dynamic learning environment, personalized support for learners becomes more important. This paper demonstrates how to realize personalized learning support in dynamic and heterogeneous learning environments by utilizing Adaptive Web technologies. We focus on course personalization in terms of contents and teaching materials that is according to each student's needs and capabilities. To accomplish this, a conceptual model based on the Knowledge Structure is presented. Using the hierarchy and association rules of the concepts, we can organize courses and lessons as a multi-layer knowledge network, which has a reasonable classification and interdependent relations among the knowledge. With retrieval based on concept and association among the concepts, we propose a framework of knowledge structure based visualization tool for representi...