problems with Nordic44-30-HV1_GL.geojson

[VladimirAlexiev]

• I converted Nordic44-30-HV1_GL.geojson to nquads at https://json-ld.org/playground/,
• saved as Nordic44-30-HV1_GL.nt
• made file prefixes.ttl because nquads doesn't retain prefixes:

  @prefix geojson: <https://purl.org/geojson/vocab#>.
  @prefix cim: <http://iec.ch/TC57/CIM100#>.
  @prefix nc: <http://entsoe.eu/ns/nc#>.
  @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>.
  @prefix dcterms: <http://purl.org/dc/terms/>.
  @prefix dct: <http://www.w3.org/ns/dcat#>.
  @prefix prov: <http://www.w3.org/ns/prov#>.

• converted to Nordic44-30-HV1_GL.ttl :

  cat prefixes.ttl Nordic44-30-HV1_GL.nt | riot --syntax ttl --formatted=ttl >Nordic44-30-HV1_GL.ttl

Problems:

• name it .jsonld rather than .geojson because it's first and foremost JSONLD, even though it also carries geo info
• WARN riot :: [line: 29, col: 89] Lexical form '2022-07-11T17:20:00' not valid for datatype XSD date
• the prefix "dct": "http://www.w3.org/ns/dcat#" is misspelt: later you use dcat, which results in an invalid URL like <dcat:version>
• the prop <dcterm:created> is misspelt: you've defined prefix dcterms. However, I strongly suggest you switch to the shorter dct, which is more commonly used
• there are 5 URLs eg "https://statnett.no/Nordic44/HV1/GL" that are rendered as strings. Render them as URLs, eg <https://statnett.no/Nordic44/HV1/GL>
• dcterms:LocationPeriodOrJurisdictionis a class not a property (the property is dct:coverage). But you better use the more specific propertydct:spatial`

---

Most importantly: you use https://github.com/geojson/geojson-ld to attach geo regions to assets, eg:

<urn:uuid:1c46e73d-6333-48ac-9367-1610caf1d3df>
        cim:IdentifiedObject.description
                "Right-of-Way Kristiansand Arendal" ;
        cim:IdentifiedObject.name  "RoW 300KRISTIAN-ARENDAL" .

<urn:uuid:ce9450ba-f145-4a83-bcbb-cc9098f4fa23>
        rdf:type            geojson:Feature ;
        geojson:geometry    [ rdf:type geojson:MultiPolygon ; geojson:coordinates (list of lists)
        geojson:properties  [ nc:RightOfWay  <urn:uuid:1c46e73d-6333-48ac-9367-1610caf1d3df> ] .

There are numerous problems with this approach:

• this is a non-standard way by "Sean Gillies" and a few other guys. It's not an OGC standard.
• It doesn't conform to OGC GeoSPARQL. GeoSPARQL 1.1 includes GeoJSON literals (https://opengeospatial.github.io/ogc-geosparql/geosparql11/spec.html#_a_3_4_geojson_serialization), but not in the way you've use GeoJSON
• Capturing coordinates as a list of lists doesn't facilitate indexing by repositories, and doesn't enable any region algebra operations (eg touches, intersects, within...). Please express coordinates as ^^geo:asWKT literals, which is one of the ways mandated by GeoSPARQL (the other is asGML)
• How would one know what to look for in geojson:properties to find the related asset?
• Why are these properties spelled with leading capital?

[Sveino]

• name it .jsonld rather than .geojson because it's first and foremost JSONLD, even though it also carries geo info

The primary reason for using .geojson is so that VSCode can do automatic validation against GeoJSON. In addtion Github does display the map information with this name. I would in general say that this is primarly a GeoJSON were we do use JSON-LD rather than JSON.

• the prop <dcterm:created> is misspelt: you've defined prefix dcterms. However, I strongly suggest you switch to the shorter dct, which is more commonly used

https://www.w3.org/TR/vocab-dcat-3/ are using dcterms, so the thinking was to be alined with latest and greatest.

• dcterms:LocationPeriodOrJurisdictionis a class not a property (the property is dct:coverage). But you better use the more specific propertydct:spatial`

So the thinking is that dct:spartial is not necessary correct. Since we are trying to refer to the area of responebility. Statnett is responseble to model the transmission network, that can be spartial overlapping with distribution. But do you think it would be OK to use dct:spartial?

Most importantly: you use https://github.com/geojson/geojson-ld to attach geo regions to assets, eg:

This is a good alternative, but the point was to be confom to GeoJSON. This does not prevent us from adding geojson-ld to the asset. The GeoJSON export is created for the export from Geographical Information System (GIS).

• this is a non-standard way by "Sean Gillies" and a few other guys. It's not an OGC standard.

The proposal is created based on examples from OGC. I have also send an email to Nicholas Car for comments. It would be really good if you can make an example that would conferm to GeoJSON.

[VladimirAlexiev]

Please read more carefully what I wrote: <dcterm:created> uses a misspelt prefix, so it's converted to a full URL with invalid scheme dcterm: rather than a prefixed URL with dcterms:.

There are two kinds of coverage: spatial, temporal. Norway is related to spatial, not temporal.

GeoJSON-LD is not any standard.

• GeoSPARQL 1.0 uses WKT and GML literals and is widely supported by repositories
• GeoSPARQL 1.1 allows GeoJSON literals: but as strings, not as RDF lists-within-lists; and is not yet supported by many repositories

I could make an example and continue with advice if we get into some engagement.