How does RDF Messages relate to KE

[bnouwt]

W3C is working on a standard about RDF Messages: https://w3c-cg.github.io/rsp/spec/messages

We should investigate whether these are somehow related to the KE.

[pietercolpaert]

I just came across this repository as I was looking for a Notation3 reasoner in Java: cool stuff!

I also happen to be the editor behind the RDF Messages spec. You might be interested in this playground that combines n3 reasoning with RDF Messages and has an example here similar to yours on Celsius → Fahrenheit: https://www.pieter.pm/rdfjs-inference-engine/#example=qudt-temperature-owl

This blog post then combines SHACL with RDF Messages and inferencing: https://pietercolpaert.be/linkeddata/2026/07/16/why-linked-data

[bnouwt]

Thanks! 😄 Internally we are currently storing our observation messages in TRIG format like the example below, but we are considering also supporting the RDF Messages format (which shouldn't be too hard I expect).

Off topic: Interesting blog-post! Where your solution uses SHACL to describe the input and output shapes, the knowledge engine uses Knowledge Interactions (KIs). Storing such shapes next to DCAT descriptions would indeed be the next step! 👍 Our reasoner uses these KIs (together with domain knowledge (i.e. triples and rules)) to come up with a reasoning plan (before looking at the actual data) to indeed solve similar problems like automatic units conversion! We will present our example and other work at Semantics 2026, if you are interested!

<http://www.example.org/graph/ae4232f5-808d-486c-8928-41d62d991f87> {
    <http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/bfd8cfbf-a4c5-4cea-b50a-b161c62852eb/result>
            a       <https://saref.etsi.org/core/PropertyValue>;
            <https://saref.etsi.org/core/isValueOfProperty>  <http://qudt.org/vocab/quantitykind/Energy>;
            <https://saref.etsi.org/core/hasValue>  "123.45";
            <https://saref.etsi.org/core/isMeasuredIn>  <http://qudt.org/vocab/unit/W> .
    <http://www.example.org/graph/ae4232f5-808d-486c-8928-41d62d991f87>
            <http://purl.org/dc/terms/date>  "2026-07-27T12:12:56.423Z"^^<http://www.w3.org/2001/XMLSchema#dateTime>;
            <http://purl.org/dc/terms/creator>  <http://www.example.org/meter/xxx200/xxx200-xxx/interaction/smart-meter-post-ki-xxx> .
    <http://www.example.org/meter/xxx200/Active_Power_L1>
            <https://saref.etsi.org/core/hasPropertyValue>  <http://www.example.org/meter/xxx200/observation/xxx-200-B09/34/bfd8cfbf-a4c5-4cea-b50a-b161c62852eb/result> .
    <http://www.example.org/meter/xxx200/observation/xxx-200-B09/34/bfd8cfbf-a4c5-4cea-b50a-b161c62852eb>
            a       <https://saref.etsi.org/core/Observation>;
            <https://saref.etsi.org/core/madeBy>  <http://www.example.org/meter/xxx200/xxx-200-B09/34>;
            <https://saref.etsi.org/core/hasTimestamp>  "2026-07-27T12:12:56.337+00:00";
            <https://saref.etsi.org/saref4ener#hasUsage>  <https://saref.etsi.org/saref4ener/Consumption>;
            <https://saref.etsi.org/core/hasResult>  <http://www.example.org/meter/xxx200/observation/xxx-200-B09/34/bfd8cfbf-a4c5-4cea-b50a-b161c62852eb/result> .
}

<http://www.example.org/graph/57057b7d-2711-4e40-941b-4e131cbff642> {
    <http://www.example.org/meter/xxx200/Active_Power_L2>
            <https://saref.etsi.org/core/hasPropertyValue>  <http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/d2604cf6-cdba-4b50-a409-2fdf660b870a/result> .
    <http://www.example.org/graph/57057b7d-2711-4e40-941b-4e131cbff642>
            <http://purl.org/dc/terms/date>  "2026-07-27T12:12:56.525Z"^^<http://www.w3.org/2001/XMLSchema#dateTime>;
            <http://purl.org/dc/terms/creator>  <http://www.example.org/meter/xxx200/xxx200-xxx/interaction/smart-meter-post-ki-xxx> .
    <http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/d2604cf6-cdba-4b50-a409-2fdf660b870a/result>
            a       <https://saref.etsi.org/core/PropertyValue>;
            <https://saref.etsi.org/core/isValueOfProperty>  <http://qudt.org/vocab/quantitykind/Energy>;
            <https://saref.etsi.org/core/hasValue>  "273.94";
            <https://saref.etsi.org/core/isMeasuredIn>  <http://qudt.org/vocab/unit/W> .
    <http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/d2604cf6-cdba-4b50-a409-2fdf660b870a>
            a       <https://saref.etsi.org/core/Observation>;
            <https://saref.etsi.org/core/madeBy>  <http://www.example.org/meter/xxx200/xxx-200-xxx/34>;
            <https://saref.etsi.org/core/hasTimestamp>  "2026-07-27T12:12:56.442+00:00";
            <https://saref.etsi.org/saref4ener#hasUsage>  <https://saref.etsi.org/saref4ener/Consumption>;
            <https://saref.etsi.org/core/hasResult>  <http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/d2604cf6-cdba-4b50-a409-2fdf660b870a/result> .
}

[bnouwt]

We've modified our internal storage-knowledge-base and made the storage format of the streams configurable. You can now choose between the above TRiG format and RDF Messages (example below).

There are other ways in which RDF Messages could be useful for the Knowledge Engine, but those will be addressed in separate issues.

VERSION "1.1-messages"
MESSAGE
<http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/bfd8cfbf-a4c5-4cea-b50a-b161c62852eb/result>
		a       <https://saref.etsi.org/core/PropertyValue>;
		<https://saref.etsi.org/core/isValueOfProperty>  <http://qudt.org/vocab/quantitykind/Energy>;
		<https://saref.etsi.org/core/hasValue>  "123.45";
		<https://saref.etsi.org/core/isMeasuredIn>  <http://qudt.org/vocab/unit/W> .
<http://www.example.org/meter/xxx200/Active_Power_L1>
		<https://saref.etsi.org/core/hasPropertyValue>  <http://www.example.org/meter/xxx200/observation/xxx-200-B09/34/bfd8cfbf-a4c5-4cea-b50a-b161c62852eb/result> .
<http://www.example.org/meter/xxx200/observation/xxx-200-B09/34/bfd8cfbf-a4c5-4cea-b50a-b161c62852eb>
		a       <https://saref.etsi.org/core/Observation>;
		<https://saref.etsi.org/core/madeBy>  <http://www.example.org/meter/xxx200/xxx-200-B09/34>;
		<https://saref.etsi.org/core/hasTimestamp>  "2026-07-27T12:12:56.337+00:00";
		<https://saref.etsi.org/saref4ener#hasUsage>  <https://saref.etsi.org/saref4ener/Consumption>;
		<https://saref.etsi.org/core/hasResult>  <http://www.example.org/meter/xxx200/observation/xxx-200-B09/34/bfd8cfbf-a4c5-4cea-b50a-b161c62852eb/result> .

MESSAGE
<http://www.example.org/meter/xxx200/Active_Power_L2>
		<https://saref.etsi.org/core/hasPropertyValue>  <http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/d2604cf6-cdba-4b50-a409-2fdf660b870a/result> .
		<http://purl.org/dc/terms/creator>  <http://www.example.org/meter/xxx200/xxx200-xxx/interaction/smart-meter-post-ki-xxx> .
<http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/d2604cf6-cdba-4b50-a409-2fdf660b870a/result>
		a       <https://saref.etsi.org/core/PropertyValue>;
		<https://saref.etsi.org/core/isValueOfProperty>  <http://qudt.org/vocab/quantitykind/Energy>;
		<https://saref.etsi.org/core/hasValue>  "273.94";
		<https://saref.etsi.org/core/isMeasuredIn>  <http://qudt.org/vocab/unit/W> .
<http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/d2604cf6-cdba-4b50-a409-2fdf660b870a>
		a       <https://saref.etsi.org/core/Observation>;
		<https://saref.etsi.org/core/madeBy>  <http://www.example.org/meter/xxx200/xxx-200-xxx/34>;
		<https://saref.etsi.org/core/hasTimestamp>  "2026-07-27T12:12:56.442+00:00";
		<https://saref.etsi.org/saref4ener#hasUsage>  <https://saref.etsi.org/saref4ener/Consumption>;
		<https://saref.etsi.org/core/hasResult>  <http://www.example.org/meter/xxx200/observation/xxx-200-xxx/34/d2604cf6-cdba-4b50-a409-2fdf660b870a/result> .

[pietercolpaert]

Nice! I’ll add that to our list of early adopters!