YOUR OPINION NEEDED!
First question
We are trying to get a better feel for how people are using QUDT. Do you...Please answer our brief poll here, then return to consider the following:
- 1. Use QUDT with the OWL schema
- 2. Use QUDT with the SHACL schema
- 3. Use just the QUDT vocabularies as persistent, unique identifiers for units, etc.
- 4. Use QUDT in some other way
Second question
For the OWL users, we are considering simplifying the OWL schema for several reasons.Before we take any action, we need to hear from you! We are considering one of the following options:
- 1. We perform all of our development and maintenance work using the SHACL schemas
- 2. We have been told that few users are actually trying to do OWL reasoning on QUDT
- 3. The OWL axioms concerning object properties is a maintenance time sink
The vocabularies are all just RDFS, so they remain untouched by this change.
- 1. Remove all axioms from the OWL schema, that is restriction classes for allValuesFrom, someValuesFrom and cardinality constraints, and perhaps a small number of other axioms. Instead adopt a version of RDFS-plus which would necessitate expressing domain(s) and range(s) on properties.
- 2. Leave things as they are, recognizing that errors occasionally creep in (e.g. try loading it in Protege right now - there are 3 errors)
Please give us feedback by entering a comment on our GitHub Discussions page here.
We will wait for your feedback until December 15, 2025 before deciding on our course of action.
QUDT.org is a 501(c)(3) public charity nonprofit organization founded to provide semantic specifications for units of measure, quantity kind, dimensions and data types. QUDT is an advocate for the development and implementation of standards to quantify data expressed in RDF and JSON. Our mission is to improve interoperability of data and the specification of information structures through industry standards for Units of Measure, Quantity Kinds, Dimensions and Data Types.
QUDT.org operates thanks to volunteers, but we do have infrastructural costs of course. If you value the QUDT ontologies as a resource available to all, please consider a DONATION of any amount (tax deductible in the USA). That will allow us to keep going and growing.
QUDT.org exists to make the QUDT Ontologies, derived models and vocabularies available to the public. Originally, QUDT models were developed for the NASA Exploration Initiatives Ontology Models (NExIOM) project, a Constellation Program initiative at the AMES Research Center (ARC).
QUDT is more than a set of vocabularies representing the various quantity and unit standards. It can be used to solve problems. Some of the associated use cases are itemized below:
The DOI reference for citations of QUDT is: https://doi.org/10.25504/FAIRsharing.d3pqw7
QUDT is comprised of several linked ontologies. The core design pattern of the QUDT ontology is shown here:
The table below provides the Base URIs for these ontologies.
| Ontology | Base URI |
|---|---|
| Main QUDT Ontology | http://qudt.org/schema/shacl/qudt |
| QUDT Datatype Ontology | http://qudt.org/schema/shacl/datatype |
| QUDT Units Vocabulary | http://qudt.org/vocab/unit |
| QUDT QuantityKinds Vocabulary | http://qudt.org/vocab/quantitykind |
| QUDT DimensionVectors Vocabulary | http://qudt.org/vocab/dimensionvector |
| QUDT Physical Constants Vocabulary | http://qudt.org/vocab/constant |
| QUDT Systems of Units Vocabulary | http://qudt.org/vocab/sou |
| QUDT Systems of Quantity Kinds Vocabulary | http://qudt.org/vocab/soqk |
QUDT is governed by a board of directors from different organizations.
Last Updated March 1, 2022
This work is licensed under a Creative
Commons Attribution 4.0 International License.