6Impelluso Tom. Physically based virtual reality in a distributed environment[J]. Computer Graphics, 1996, 30(4): 60-61.
7Knezevic J, Odoom E R. Reliability modeling of repairable systems using Petri nets and fuzzy Lambda-Tau methodology[J]. Reliability Engineering and System Safety, 2001, 3(73): 1-8.
8Eriksson E Optimizations of a bus body structure. Heavy Vehicle Systems[J]. Heavy Vehicle System, 2001, 8(1): 1-16.
