SST Core is optimized in various ways for speed and efficiency.  As a result of the the SST Core is not a general purpose RDF toolkit. This mean, every RDF file generated with SST-Core is valid according to the W3C standards, but not every RDF file can be imported into SST Core. 

In detail the limitation ares.

Semantic STEP Technology (SST) is a novel way to represent, integrate and manage industrial product data as it is used in CAD, CAM, PDM, PLM, ERP and other CAx system. SST is optimized to work on the Internet using cloud computers. Major components of the SST Core are:

EDM Engineering Data Management ...

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