Ontology: Add axiom to `portions of matter` describing its relation to `state of matter`

[l-emele]

Description of the issue

The class portion of matter is currently defined as: _A portion of matter is a part of a material entity that has a state_of_matter property._ This implies a relation the the class state of matter.

Ideas of solution

Add axiom: 'has state of matter' some 'state of matter'

Workflow checklist

• [ ] I discussed the issue with someone else than me before working on a solution
• [ ] I already read the latest version of the workflow for this repository
• [ ] The goal of this ontology is clear to me

I am aware that

• [ ] every entry in the ontology should have a definition
• [ ] classes should arise from concepts rather than from words

[l-emele]

A minor thing, that should be fixed, too: The term tracker item of portion of matter is currently:

issue: https://github.com/OpenEnergyPlatform/ontology/issues/227
pull request: https://github.com/OpenEnergyPlatform/ontology/pull/279

This is simply wrong. This class was already discussed in issue #45 and implemented in PR #58.

[l-emele]

I just spotted a further thing: The current definition does not mention its direct parent class which is object aggregate. That should be fixed, too. Also the uncountable aspect of the portions of matter are not part of the definition. Therefore I propose to update the definition to:

_A portion of matter is an object aggregate of an uncountable number of material entities that have a state of matter property._

[stap-m]

I agree, that such an axiom makes sense.

About the definition: I remember vaguely that we didn't use the Aristotelian def here on purpose to make the portion of matter concept easier to understand. But I'm also ok to change it now for consistency reasons.

[l-emele]

@OpenEnergyPlatform/oeo-general-expert-formal-ontology : Do you have any opinion on changing the definition of portion of matter?

[jannahastings]

Hmmm. We could try the slightly more readable _A portion of matters is an aggregate of material entities that have a state of matter._ ?

[jannahastings]

Maybe it needs saying that it is an aggregate of material entities of the same type

[stap-m]

Maybe it needs saying that it is an aggregate of material entities of the same type

I think "same type" is hard to define. "Same type of molecule" would exclude air, for instance.

I like Jannas proposal. Should we include the "uncountable" property of portion of matter to the def (is that true btw)?

[l-emele]

Should we include the "uncountable" property of portion of matter to the def (is that true btw)?

That was at least the start of the discussion in #45 and the reason why we introduced portion of matter in the first place.

[l-emele]

Maybe we don't need the _uncountability_ in the definition but I think we should at least mention it in an editorial note or something like that. And we could also point in such a note to our explanation in the wiki: https://github.com/OpenEnergyPlatform/ontology/wiki/Explanation-on-mass-nouns

[l-emele]

Proposal for editorial note: _Portions of matter describe mass nouns like water, air and fuel. Mass nouns are uncountable but portions of these can be quantified like 1 glass water, 1 m³ air or 1 barrel of fuel. For further explanation please refer to: https://github.com/OpenEnergyPlatform/ontology/wiki/Explanation-on-mass-nouns_

[stap-m]

Sounds good. ...shouldn't it be: "1 glass of water, 1 m3 of air"?

[l-emele]

Yes, of course.