[sdw] reuse of SSN for static (aka nominal) properties (#1449)

valecarriero has just created a new issue for https://github.com/w3c/sdw:

== reuse of SSN for static (aka nominal) properties ==
Hi,

we are reusing and extending SOSA and SSN for modelling Hydrogen Valleys. 
See https://w3id.org/h2v and https://w3id.org/h2v/property for the first version of the ontology (we are currently working on some changes/extensions).

- In our use case, we needed to model both static and dynamic properties of some Hydrogen Valley's components. 
- By dynamic properties we mean "a time-varying property of a system that is dynamically observed or measured": we believe this is perfectly covered by the SOSA classes for ObservableProperties and Observations. 
- Instead, a static property (also called nominal property) is a property that is typically defined by design or manufacturer specifications and is not meant to be dynamically observed: we believe this is not completely addressed by SOSA+SSN (at least, not in its current stable version). 
- Being the definition of `ssn:Property` quite generic ("A quality of an entity"), we decided to create a subclass of `ssn:Property`, namely `h2v:StaticProperty`, to which is directly linked a `qudt:QuantityValue` through the property `h2v:hasStaticValue`. `qudt:QuantityValue` is then linked to a `qudt:Unit` and to a `qudt:numericValue` or `schema:minValue`/`schema:maxValue` for expressing ranges. See image at the end.

We wanted to be sure that we are reusing and extending SSN in a proper way. 
As far as we understood by looking on the web, this topic of "nominal property" has already been discussed in the community, but we are not sure if/how it is addressed in the latest published version https://www.w3.org/TR/vocab-ssn/, if/how do you plan to address it in possible future versions (https://w3c.github.io/sdw-sosa-ssn/ssn/ ?) and if we are correctly implementing it. 
It seems to us we did something similar as SAREF, but we could not find direct alignments of SAREF to SSN. 

N.B.: I am opening this issue also on the https://github.com/w3c/sdw-sosa-ssn repository.

Thank you,
Valentina

<img width="2624" height="1584" alt="Image" src="https://github.com/user-attachments/assets/2fad32cb-c48e-40d9-b30b-9b68a263a7c0" />

Please view or discuss this issue at https://github.com/w3c/sdw/issues/1449 using your GitHub account


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Received on Friday, 11 July 2025 15:03:06 UTC