Wrong conversion factors

[jmkeil]

Using a comparison of unit ontologies with ABECTO I became aware that the following units have wrong conversion factors:

• http://www.ontology-of-units-of-measure.org/resource/om-2/faraday: 9.648531e4
• http://www.ontology-of-units-of-measure.org/resource/om-2/ton-Register: 2.831658 (transposed digits)

Further there might be wrong values at the following units, but I am not able to decide upon without further investigation:

• [ ] http://sweetontology.net/reprSciUnits/year with 3.1556926E7" vs. 3.1536e7 by http://www.ontology-of-units-of-measure.org/resource/om-2/year vs. 31557600 by http://qudt.org/vocab/unit/YR (probably different definitions have been used)
• [ ] http://qudt.org/vocab/unit/BTU_MEAN with 1055.05585262 vs. 1.05587e3 by http://www.ontology-of-units-of-measure.org/resource/om-2/BritishThermalUnit-Mean
• [ ] http://qudt.org/vocab/unit/CAL_15_DEG_C with 4.1855e0 vs. 4.18580 by http://www.ontology-of-units-of-measure.org/resource/om-2/calorie-15C
• [ ] http://qudt.org/vocab/unit/CH with 20.1168 vs. 2.011684e1 by http://www.ontology-of-units-of-measure.org/resource/om-2/chain

[HajoRijgersberg]

Thanks so much, Jan Martin! I'll dive into it and correct it, this week! I'll keep you up to date!

[HajoRijgersberg]

Hi Jan Martin,

I am first diving into the Faraday, but I am not sure about its value. Wikipedia says it's 96485.33212... C (https://en.wikipedia.org/wiki/Faraday_constant#Faraday_unit_of_charge) and Sizes indicate it's equal to 96 485.3399 ± 0.0024 C (https://www.sizes.com/units/faraday.htm). Google says its 96 485.3329 C. And if you google on 'faraday 9648531' you find many sources that indicate that the value is 9.648531e4, the value currently defined in OM. So, I am not sure, and will for the time being remove the value entirely from OM. I hope to do that tomorrow (times are very busy nowadays). Happy to read your response! :)

Best, Hajo

[HajoRijgersberg]

And as to the register ton, do you have a reference that indicates the true value? I can only find rough indications, e.g. on Wikipedia, that say it's 2.83 m3. Google indicates a (much) more precise value, but a reference is missing (or I can't find it). Looking forward to your response! Thanks in advance! :)

[HajoRijgersberg]

I have just uploaded a new version of OM, where I removed the definitions (i.e., factors and units) of the faraday and register ton.

[jmkeil]

And as to the register ton, do you have a reference that indicates the true value? I can only find rough indications, e.g. on Wikipedia, that say it's 2.83 m3. Google indicates a (much) more precise value, but a reference is missing (or I can't find it). Looking forward to your response! Thanks in advance! :)

I did not find an official source by now. However, many pages I found state, that register ton is defined as 100 cubic foot:

1 register ton = 100 foot³ = 100 * (0.3048 m)³ = 2.831 684 659 2 m³

• https://en.wikipedia.org/wiki/Gross_register_tonnage
• https://www.thefreedictionary.com/register+tons
• http://conversion.org/volume/register-ton/
• https://de.wikipedia.org/wiki/Registertonne
• https://www.wikidata.org/wiki/Q752079

[HajoRijgersberg]

I have corrected the register ton (om:ton-Register) (2.8316846592 m3). I also dived into the other possible inaccuracies you detected and corrected the year (31556952 s) and the chain (20.1168 m). BTU's and calories appear to be more complex, hence I have to study them more deeply. So, for the time being I have removed their conversion/definition factors and units. So once again, thank you very much Jan Martin, for detecting these inaccuracies and possible inaccuracies!