5[1]WEST M. An overview of the modularization, SC4 framework, and SC4 data architecture Projects[EB/OL]. http:∥www. nist. gov/sc4/wg-qc/wg10/current/n291/wg10n291. pdf,2003-04-15.
6[2]METZGER F. The challenge of capturing the semantics of STEP data models precisely. Harold Boley. Workshop on product knowledge sharing for integrated enterprises [EB/OL]. http:∥www. ladseb. pd. cnr. it/infor/Ontology/BaselPapers/Metzger. pdf, 2003-04-15.
7[3]GRUBER T R. A translation approach to portable ontology specifications [J]. Knowledge Acquisition,1993,5(2) :199-220.
8[4]BERNERS-LEE T. Weaving the Web [M]. San Francisco: Harper, 1999.
9[5]LASSILA O, SWICK R R. Resource Description Framework (RDF) model and syntax specification[EB/OI]. Http:∥www. W3. Org/TR/REC-rdf-syntax/,2003-04-15.
10[6]BRICKLEY D, GUHA R. RDF vocabulary description language 1. 0: RDF Schema [EB/OL]. Http:∥www.w3. Org/TR/rdf-schema/, 2003-04-15.
