The semantic object data model is defined by {HEAD ~ one or more semantic objects}, {TAIL ~ each} of which includes one or more attributes that describe a characteristic of the semantic objects 
The semantic object data model is defined by { HEAD ~ one or more semantic objects } , { TAIL ~ each } of which includes one or more attributes that describe a characteristic of the semantic objects
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH