#rdfs — Public Fediverse posts

Ik zie dat de Nederlandse #overheid ( @Logius ) de #TOOI ontologieën en thesauri online te raadplegen heeft gemaakt via #ShowVoc. Heel cool!

https://standaarden.overheid.nl/showvoc/#/datasets

Al deze informatie kan ook via een SPARQL-endpoint benaderd worden. En #WikiData federeert sinds kort met het TOOI SPARQL-endpoint.

#LinkedData #thesauri #RDF #OWL #SKOS #RDFS #SPARQL #ontologie #overheidsinformatie #metadata

Scrolling past the Royal Flying Doctor Service website for the 100th time as I Google for the RDF Schema documentation

#semanticweb #rdf #rdfs #owl

@multimeric I think they serve different purposes. #rdfs is not really a schema language, at least not in the "here is a prescribed structure you can validate against" sense. It was more intended as a descriptional thing, something to define basic vocabulary ("my model is about kinds of vehicles, like cars, and bikes"). A lightweight ontology language if you will. SHACL is about setting structure constraints, and data validation. They're complementary IMO.

RDF people: why does everyone still use RDFS and not SHACL for writing schemas, when all the actual validation tools are for SHACL?

Are there even any RDFS validators? I can't find any.

#rdf #semanticweb #rdfs #shacl

Version 1.0 of the JavaScript #shacl library shacl-engine is out. here are no breaking changes, only new features, but to indicate that this package is production ready, the version was lifted from 0.x to 1.x.
via ThomasBergwinkl@LinkedIn @bergi

https://github.com/rdf-ext/shacl-engine

#shack #semanticweb #sparql #rdf #rdfs #javascript

In the #ISE2024 lecture today, we will discuss RDF as basic building block for the Web of Data.

slides: https://drive.google.com/file/d/1gJ3RD3Sz2JuEpCF-mBBfA85boYP_jrON/view?usp=drive_link

#semanticweb #knowledgegraphs #rdf #rdfs #WebOfData @fizise @MahsaVafaie @enorouzi @shufan @sourisnumerique

@hrefna you're so deeply right in this thread. this essentially defines the early and formative years of #RDF and #RDFS around some key decisions. There is so much worry about errors from mishandling, but the very possibility of expressing something that could be wrong. There is so much here it's hard to even know where to start but from the very start of the rdf-core and especially rdf-logic mailing lists the emphasis on correctness of expression vs. agency of interpretation is heated. This is a pretty unsubtle example: https://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001Nov/0423.html

"Summary: RDF is not just a data model. The RDF specs should define a semantics so that an RDF statement on the web is interpreted as an assertion of that statement such that its author would be responsible in law as if it had been published in, say, a newspaper."

affirmed by this text: https://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jun/0180.html

"The RDFCore WG takes the view that RDF/XML documents, ie. encodings of
RDF graphs, are represenations of claims or assertions about the world. [...] we note that RDF graphs are the kind of things that can be true or false (rather than 'mere bytes'). For each linear syntax of RDF, there will be conventions (social, legal) for indicating which chunks of data are encodings of RDF graphs in that syntax, and thus of propositional content."

So ya very very early they had decided that RDF was intended to be platonic representation of the world - it is a method of making propositions that must directly bear on the world, there is no ambiguity, there are only true or false things. (There's a lot of subtlety in that but yno.)

Another thing that comes to mind is the discussion of monotonicity that happens throughout, that's also tied up with the discussion of closed worldedness, containers, and whether or not things belong in sets for the purpose of local meaning or need to belong to the One Great Uniform Graph. It must be impossible for adding new triples into the reasoner to make it less certain of some outcome (ie. if it was possible for ambiguity to be introduced eg. by tangled type hierarchies etc.). This thread is all very illustrative but this message is super spicy and also touches on what you're talking about re using the level of granularity you care about: https://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001Nov/0363.html

this quote from D bricks is also pretty telling of the epistemological commitments:
"RDF Schema is not about policing the content of specific descriptions
'what is said'; it's about policing what is sensibly sayable."

#RDFS has a generic container type
And RDFs has a label property to set something's name.
And skos has a canonical sameAs property.

And containment indicates relative location
And a location relative to an absolute location has an absolute location.
And multiple routes to a location can be indicated to be the same object.

So why are there all these damn bnodes in my JSON-LD representations

In the next section in this week's #kg2023 online lecture you will learn about vocabularies and how to design simple models with the RDF Schema Description Language RDFS.
video lecture: https://open.hpi.de/courses/knowledgegraphs2023/items/2fLyYCsLoiikZJCuCjjspY
#OpenHPI @fiz_karlsruhe @fizise @tabea @sashabruns @enorouzi #knowledgegraphs #mooc #lecture #semanticweb #rdf #rdfs #startrek

@alexl in a graph database, schemas are generally very flexible. From "data blocks" to just attaching your own graph structures… lots of options.

Personally I would want this to happen. Real knowledge graphs profit from holistic networking. If we can add a whole semantic ala #RDFS then we‘d really be starting to go off on the races…

rdfs:isDefinedBy might be a good in-between for owl:sameAs (too strict semantics) and rdfs:seeAlso (too vague).

#lod #owl #rdfs #semantics

Announcing Aidan Hogan and Sebastian Rudolph for the first tutorial session on querying and reasoning on #knowledgegraphs at #isws2023

#SPARQL #RDF #RDFS #SemanticWeb #GraphDatabases

Ich @chpollin unterrichte auch am ZIM in Graz zum Thema Semantic Web. Meine Lehrmaterialien können gerne verwendet werden. Es gibt Folien und Screencasts zu #RDF, #RDFS, #SPARQL und #Ontology: https://github.com/chpollin/Teaching/tree/master/InfoMod

Screencasts auf YouTube: https://youtu.be/reLxbnYVZbY

(alle CC-BY)

@divclassbutton @zizaco @hanshuebner
VHS was the inferior option that took off because of industry adoption rather than technical merit.

When I was considering how painful I find it to work with JSON (I deal with #telemetry feeds pushing TBs of #JSON data every day) I was not thinking of #XML as the alternative. I would prefer strongly typed binary encodings like #Avro or #ProtoBuf.

And for sheer expressiveness, strong-typing and open-ended extensibility I would pick #RDFS.

Via @morganclaypool : The first two editions of "Semantic Web for the Working Ontologist" (@jahendler et.al.) describe #SemanticWeb standards and how they work, their goals, and why they were designed as they are. The third edition builds on this foundation to bring Semantic Web practice to enterprise. https://t.co/7gOsVSYljR #Modeling #OWL #RDFS

Summarized all the terms
Habe mal alles zusammengefasst ;)

• ActivityStreams2,
• Official ActivityVocabulary extensions
• Extensions defined in implementations docs
• Terms arrived in inboxes
• Other useful CV or subtypes

#rdfs #skos #owl #activitypub
https://redaktor.github.io/vocab/index.en.html

---
PS AP meeting later today
http://socialhub.activitypub.rocks/t/developers-meeting-7-a-standard-way-to-query-in-activitypub/2488
#fediverse

Q: What is a Language? A: Read: #RDF #SPARQL #SQL #OWL #RDFS #SemanticWeb #LinkedData #SmartData #OpenData #BigData