Unit request: m/min
Closed this issue · 6 comments
Hi,
I would like to request a new UnitOfMeasure: metre per minute, centimetre per minute & millimetre per minute. There are already multiple units of measure describing speed (MetrePerSecond), but in machineering often velocities are described as a distance in function of a minute.
For example:
@Prefix om: http://www.ontology-of-units-of-measure.org/resource/om-2/.
@Prefix rdf: http://www.w3.org/1999/02/22-rdf-syntax-ns#.
@Prefix rdfs: http://www.w3.org/2000/01/rdf-schema#.
@Prefix xsd: http://www.w3.org/2001/XMLSchema#.
om:MetrePerMinute rdf:type om:UnitOfMeasure ;
rdfs:label "metre per minute"@en ;
rdfs:label "meter per minuut"@nl ;
rdfs:comment "Metre per minute is a unit of speed defined as metre divided by a minute."@en ;
om:symbol "m/min"^^xsd:string ;
om:alternativeSymbol "m min-1"^^xsd:string ;
om:conversionFactorToReferenceUnit "0.016666666666666666"^^xsd:decimal ;
om:hasDimensionVector om:ISQ-Dimension-Length-Time-1 ;
om:hasReferenceUnit om:MetrePerSecond .
Hi, thanx, good suggestions! I'll add them end this week, would that be sufficient?
As to the conversion factor, that should be determined dynamically from the mathematical UnitDivision relation between the two units (e.g., metre and minute) and their hasFactor and hasUnit properties. As a side remark: I have plans to define these for all units in OM (so they don't have to be determined dynamically by the user), but this is not yet the case.
Hi,
I didn't expect a response back so quickly! By the end of the week is plenty in advance, thanks a lot! We are probably going to use this ontology within a context of machineering & welding combined with automation (PLC, motion controllers, robots). We got a lot of strange units available: some of them are brought to life because of rounding factors. For example: store a distance as decameter because it gives the right amount of precision within the available datatype. Having an ontology like this one available speeds up our development.
As a side remark: I have plans to define these for all units in OM (so they don't have to be determined dynamically by the user), but this is not yet the
I didn't understand this side remark to the fullest. Does this mean that there will be a unit available for every combination? For example: nanometer/nanosecond, millimeter/hour, millimeter/minute, and so on?
Hi, thanx for your interest! :) Yes, my response was quick as I coincidentally saw your message and defining such units for me is a relatively easy thing to do, and a grateful thing to do. And important too.
Interesting, about the precision. Presently we are discussing precision, in another issue. A good reason to use such units, I would say.
No, the side remark meant that I would like to define unit conversions for every compound unit (e.g., m/s, m2, etc.) in the future explicitly, rather than that they can only be determined dynamically through rules such as mentioned above. And I would like to include multiple unit conversions for all units. Now e.g. inch is only defined in terms of metre in OM, I would also like to specify the conversion rule to yard, parsec, etc.
Defining all combinations of metre multiples and time units such as you give as examples is also an important thing that should be done in the future in OM. Everything on the to-do list. :) But first I'll define the three examples you mentioned in your first message. ;)
Just added them! :)
Could you perhaps have a check? Many thanx in advance!
I've checked them, tested them out & they work perfectly. Thanks a lot!
Thanx for trying and your message! :)
Cheers, Hajo