- From: Pat Hayes <phayes@ihmc.us>
- Date: Mon, 18 Jan 2010 10:59:26 -0600
- To: Kjetil Kjernsmo <kjetil@kjernsmo.net>
- Cc: semantic-web@w3.org
On Jan 18, 2010, at 10:28 AM, Kjetil Kjernsmo wrote: > On Monday 18. January 2010 12:43:57 Axel Polleres wrote: >> As for units: Is there any reason why rdf:value could not solve your >> problem? (Although I admit that it might not be as widely used and it >> would be good to give it more weight, or resp. refine and push best >> practices in this direction more) > > Mainly that it has its complexity in the wrong places :-) (OK, I > admit, I > had forgotten about it, I have never seen anyone use it. > Pragmatically, > when something has so many use cases, yet seen very little use, it > is often > because its design is flawed). > > The unit is a property of the literal, not a property of the > resource. By > requiring another node, it makes it harder to query, harder to write, > harder to read and harder to understand. But how else would you naturally express a property of anything in RDF, than by writing a triple? It sounds like you want to not be using RDF at all :-) > > Also, how would you formulate a conversion between units (e.g. lb to > kg)? > Or use derived units (e.g. watt = joule / second)? That's complexity > we > should tackle, not additional triples. In another life, I am, with many others, working on an ontology for measures and units, which will among other things define a large number of conversions and unit/dimension derivations. It is quite complicated to state these, and certainly well beyond the expressive capabilities of RDF or even OWL. I don't think that this should even be contemplated as an RDF built-in feature. Pat Hayes > > Cheers, > > Kjetil > -- > Kjetil Kjernsmo > kjetil@kjernsmo.net > http://www.kjetil.kjernsmo.net/ > > ------------------------------------------------------------ IHMC (850)434 8903 or (650)494 3973 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32502 (850)291 0667 mobile phayesAT-SIGNihmc.us http://www.ihmc.us/users/phayes
Received on Monday, 18 January 2010 17:00:29 UTC