In this system, because each educational object is defined based on the CORBA model, any object can be placed on any node and transparently accessed on the network. Moreover CORBA is a substantial standard and we will be able to utilize various CORBA services which are currently being developed, such as naming service, event service, and life cycle service.
Our proposed collaborative educational system allows several students in distant locations to share a virtual three-dimensional space. The system maintains a consistent status between objects located on distributed nodes in the network by using an efficient communication method. Each constituent object of the virtual three-dimensional materials is defined as a derived sub-class of a distributed object based on the OMG-CORBA model. A new object can be created and its properties can be modified by a student. Evaluation of our prototype system showed that this system has a promising performance level, while it maintains the consistent status in a virtual room. We are planning to develop a more user-friendly interface and an efficient authoring tool for materials. We will then apply it in more practical educational situations.
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Katsumi Hosoya, Akihisa Kawanobe and Susumu Kakuta: NTT Information and Communication Systems Laboratories, Nippon Telegraph and Telephone Corporation, 3-9-11, Midori-cho, Musashino-shi, Tokyo 180 Japan.
katsumi @ isl.ntt.co.jp, nobe @ isl.ntt.co.jp, kakuta @ isl.ntt.co.jp.
Munish Sharma: Department of Electrical and Computer Engineering, 10 King's College Road, Toronto, Ontario M5S-3G4 Canada.
sharmam @ ecf.utoronto.ca.