Could you help me by simply summarizing the relation between Brick and Haystack? How do they coexist together?

Thanks! Samuel

First of all, I want to confirm that Project-Haystack.org looks to have a cooperative relationship with different organizations tackling the semantic modeling channel in the built environment. We lead the effort to work together with ASHRAE BACnet and Brick to collaborate and identify areas for cooperation and compatibility. If you haven’t seen it here is the announcement from 2018: https://marketing.project-haystack.org/project-haystack-media/ashraes-bacnet-committee-project-haystack-and-brick-schema-collaborating-to-provide-unified-data-semantic-modeling-solution

Our approach to helping people evaluate the best solution to address the challenge is to build the community, extend the standard, and publish materials that help people understand the challenge, the concepts, Haystack technology and the wide-spread adoption of Haystack around the world. We do not attempt to publish a comparison matrix as we do not see that as a useful fit for evaluation.

One thing I will point out is that as you do your evaluation there is incorrect information published by Brick regarding Project-Haystack. We suggest looking to Brick for information on their technology and Project Haystack resources for ours. We recommend these resources:

Case studies, customer adoption, media: https://marketing.project-haystack.org/

Community discussion forum, working groups: https://www.project-haystack.org/ (you of course posted on this site)

Haystack 4 developer website: https://project-haystack.dev/

Note: This will be merged with the original https://www.project-haystack.org/ site in the future.

Also, here are some relevant and posts:

https://marketing.project-haystack.org/blog/project-haystack-announces-important-new-resource-called-examples

Commentary from NREL: https://smartlabs.i2sl.org/cs-nrel-data-analysis.html

I will leave it to other members of the community to offer their thoughts.

In people's minds they coexist by working on very similar problems of classifying and relating content in the domain of HVAC by a some model. The "native" way of describing the terms and components in Haystack is with its Def model collections of dicts, the "native" way of describing concepts in Brick uses RDF, the framework of the Semantic Web. There are lots of places where they are similar, and lots of places where they are different.

The technical side of coexisting is a simple matter of extracting the Haystack content as RDF, formatted as Turtle or JSON-LD, and dropping it into your Enterprise Knowledge Graph (Virtuoso, GraphDB, Blazegraph, Stardog, AnzoGraph, AWS Neptune, or hybrid store like MarkLogic). For Cornell that world has building stuff from our Facilities Inventory system, maintenance stuff from Maximo, occupant (researcher) stuff from Workday, student stuff from SalesForce, classroom schedules from 25Live, etc.

That's the easy part.

The much harder part is recognizing when a "thing" that has some collection of tags in Haystack is in reality the same thing that has a specific name in Brick or the Google Digital Buildings Project or SAREF or Real Estate Core, etc.

The work of (1) establishing a "ground truth" of where "things" are and how they are related to enable (2) the process of aligning the taxonomies of Haystack and these other ontologies is the work of ASHRAE 223P. If you have the time and the idea of digging into the details of the definitions of things like from the buildingSMART Data Dictionary doesn't scare you off, we'd love to have you!