Re: [unitsml] units to consider for Enumerated Root Unit list

["Martin S. Weber" <martin.weber@nist.gov>]

[resent to list after I included all sorts of people on CC but forgot the list 
in To... -M]
On 08/25/11 14:13, dragoset@nist.gov wrote:
> Dear colleagues,
  > (...)
> Comment: In the Enumerated Root Unit (eru) list, we have many "us_xxx" units.
> We have only 5 imperial units: gallon, gill, ounce, pint&  quart.
> Should we add more "imperial_xxx" units?

No comment on that, given my lack of personal experience in the imperial 
worlds (UK, US, Rome, ...)

  From the list most entries do not strike me as worthy for the enumerated 
root units list, frankly. Exceptions: fathom (in use by navies), gold ounce 
(saving our savings), light hour, minutes, seconds (might be easier to use for 
derived units than trying 1/31557600th of a light year).

Makes me think:

dozen. Is this a counted-item-as-unit with a conversion factor of 12? But a 
dozen of what? Of things that are on the quantity side of that 
counted-item-as-unit? How would you (try and) model that?

baud: Yes, it's a derived unit, but not of something that we have in the ERU 
list. (yeah it's per second, but it's an abstract notion per second: symbol 
changes; whereas a symbol change can convey different amounts of information). 
Because of this, baud should make it to the list.

dots per inch: Well, we do know dpi's, we even have printers pica in the list. 
We don't have dot's though. For the sake of a conversion, dpis might
be interesting, but I'm not sold on that at all.

ppm, percent, per mille: derived / relative, but vague. Especially percent, 
permille seems hard to define. I see potential for deriving from it.

pond: I want one.

Regards,

-Martin