Introduction

The way to go in today's ICT is "data centric". When I see what that means is, at best, sets of triples put together in a Named Graph or the like. ISO 15926-7/8 has a different approach: "information centric".

How it is done?

In ISO 15926 so-called Templates are defined and used for ALL representations of information.
A Template has two parts:

• a model based on the upper ontology of ISO 15926-2 ;
• a "signature" that is an n-ary relation with the Template instance as the common rdfs:subject, and two to many relations with the variables of the model as rdfs:object.

Those relations represent the Roles that are played, by those variables, in the information represented by the Template instance.
This is why this information is "information-centric", its semantics are integrally defined. In this website you can find 200 Template Specifications here that cover the information I have come across, amongst others by mapping the CFIHOS data model.

The internal model of a Template usually is rather simple, but occasionally rather complex, but the signature is, except for one Template, never larger that nine Roles.

A temporal part of vessel V-101 has a Property that is classified as MASS of '30.57' as quatified on the Scale METRIC TON, effective 2021-11-15T13:45:00Z

with the following "signature":

ex:fcbfda39-4d1a-4047-b4ca-45ab8d44fca4
      rdf:type tpl:IndividualHasPropertyWithValue ;
      tpl:hasPropertyPossessor ex:847931fd-eade-4beb-b07d-a9e889611c19 ; # V-101
      tpl:hasPropertyType rdl:RDS353339 ; # MASS
      tpl:valPropertyValue "30.57"^^xsd:decimal ;
      tpl:hasScale rdl:RDS2229868 ; # METRIC TON
      meta:valEffectiveDate "2021-11-15T13:45:00Z"^^xsd:dateTime .

What are these referring to?

That can be:

• declared objects, discussed here;
• reference classes, defined in the RDL (Reference Data Library), an extension of the ISO 15926-4 classes, based on ISO 15926-2 entity types;
• reference classes, defined in an RDL extension;
• XML Schema Literals, e.g. date, dateTime, string, decimal, etc;
• and sometimes: template instances, mainly for information views;

This can be illustrated as shown below:

Here is an example of such a view, the set of declared objects and template instances that together (partly) define an Asset Requirements Class:

ex:a8f26f3b-766f-4ff2-b388-97918a11a133
      rdf:type tpl:EnumerationOfClass ;
      tpl:hasSet ex:c8cd9099-a5b0-47ea-a74d-7682aa0c3ed6 ; # Information set for CO_B14-P101-rev0
      tpl:hasMember 
		ex:58d5d18d-4828-4895-8765-f9c19471bc9f, # CO_B14-P101-rev0 - DECLARATION
		ex:f8053b96-efeb-4786-945f-ec91b1777813, # CO_B14-P101-CASE-rev0 - DECLARATION
		ex:17c1c3c9-cbe0-4dab-b787-b9f7b700262b, # CO_B14-P101-IN-rev0 - DECLARATION
		ex:c1d6f145-ff11-4381-9aa1-8b22a29e86c9, # CO_B14-P101-OUT-rev0- DECLARATION
		ex:8075dbb2-14d1-4394-9b7b-9c4a6449cd87, # CO_B14-P1O1-rev0 specialization of CO_B14-P101-FO-rev0
		ex:75896db5-3bc4-495f-977f-514ede4caf59, # CO_B14-P1O1-rev0 specialization of CENTRIFUGAL PUMP
		ex:abff06bf-0b30-4b7d-ab4f-1be7ab3d092c, # CO_B14-P1O1-IN-rev0 specialization of INLET NOZZLE
		ex:3dd18be8-d65a-4177-996a-27145a870892, # CO_B14-P1O1-OUT-rev0 specialization of OUTLET NOZZLE
		ex:9c1520ce-b9c2-413b-8c3e-d662a7a62aa9, # CO_B14-P1O1-IN-rev0 specialization of FLANGED END RAISED FACE ASME B16.5 CLASS 900 NPS 4
		ex:2d81cc4f-ff0e-4bc9-9b3e-800c4d27739e, # CO_B14-P1O1-OUT-rev0 specialization of FLANGED END RAISED FACE ASME B16.5 CLASS 900 NPS 4
		ex:db668dad-edd0-4e5b-9bc1-4a867287d51b, # CO_B14-S-P101-CASE-rev0 -  UPPER LIMIT ALLOWABLE WORKING PRESSURE @ NORMAL OPERATING TEMPERATURE
		ex:bac8d6d4-d8dc-4fce-ac6e-8a2e1bebc353, # CO_B14-S-P101-CASE-rev0 - HYDROSTATIC TEST PRESSURE
		ex:d003e18c-1b4e-41a4-b230-1fc2be958eed, # CO_B14-P101-rev0 referred to on particular PUMP SPECIFICATION
      meta:valEffectiveDate "2022-02-08T16:19:00Z"^^xsd:dateTime .

In this way you can define whatever view you want, for example some kind of report, or an input information set for some activity.

Metadata

It is possible to add, next to the mandatory meta:valEffectiveDate, any metadata that you require.
Examples are: skos:changeNote, skos:historyNote, meta:annAccessCode, meta:annRule, dc:source, etc