Thank you very much.

The latest turtle file is on the Haystack 4 defs website here. Or you can use this link directly.

Note: we recently changed the prototypes from strings to dicts, which is yielding some ugliness in the RDF model for those. So we need to fix that

Thank you for your quick reply. I tried to understand the online document but still have questions. Is the defs.ttl the haystack ontology file?

I am new to rdf.

Thank you very much.

Does defs.ttl defines the haystack classes, object properties and data properties? By that I mean if we can see all the entities and their relations of haystack in defs.ttl?

Does Tag == haystack classes?

Thanks,

-xiaoshan

If you are new to RDF, then I would not start with that mental model nor worry about the turtle data files. Especially if you are a programmer its easier to think about the model as hashmaps or JSON objects. Each key/value pair defines a fact about the entity (equip, point, etc).

Marker tags are essentially used to define your types/classes. For example if you have the elec and meter marker tags, then you implement the elec-meter equipment "class".

Value tags define property data such as the area tag defines the square footage/meters of a building.

Relationships are pretty much just like RDBMS or RDF - they are a name/value pair that references another entity. The name of the tag defines what the relationship means.

1. Do you have visualization for haystack ontology?
2. I tried to parse the haystack ontology using Jena, to visualzie the classes and their relations in neo4j. I used defs.ttl. I found there are more than 400 classes and much less object properties. I donot know if I am correct.

Is there any documents I can reference for my task?

Thanks, -xiaoshan

Most the terms in the Haystack 4 ontology are markers and conjuncts which map to RDF classes, so that is what you would expect.

Probably the most important piece of the entire ontology to visualize is the taxonomy of the equip types which you can see here as an HTML tree.

The Haystack 4 doc pages have a bunch of indices which show various taxonomies which is a good way to understand the various concepts and how the class hierarchies are structured