PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Reference signals having angular frequencies of 2?? and 4?? are generated, one of these signals being employed to synchronously detect the signal at the output of the photodetector by adjusting the quarter-wave plate until the synchronously detected signal component is zero, the orientation of the quarter-wave plate then corresponding to the polarization parameter ??.
http://www.w3.org/ns/prov#wasQuotedFrom
  • google.com