About: http://webisa.webdatacommons.org/81052227

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Your GPS is an example of such a target which does the calculation by reading satellite signals containing timestamps allowing the device to calculate how far it is from each satellite.
http://www.w3.org/ns/prov#wasQuotedFrom	delphiforfun.org