Re: URIs / Ontology for Physical Units and Quantities

Ralph,

QUDT:

>From https://wrdrd.github.io/docs/consulting/knowledge-engineering#qudt

> Homepage: http://www.linkedmodel.org/doc/qudt/1.1/
> Standard: http://qudt.org/
> Namespace: http://qudt.org/schema/qudt#
> xmlns: @prefix qudt: <http://qudt.org/schema/qudt#> .
> LOVLink: http://lov.okfn.org/dataset/lov/vocabs/qudt
>
> QUDT (*Quantities, Units, Dimensions, and Types*) is an *RDF*
> <https://wrdrd.com/docs/consulting/knowledge-engineering#rdf> standard
> vocabulary for representing physical units.
>
>    - QUDT is composed of a number of sub-vocabularies
>    - QUDT maintains conversion factors for Metric and Imperial Units
>
>
A few JSON-LD examples could be very helpful.


On Thu, May 7, 2015 at 7:21 AM, Ralph TQ [Gmail] <rhodgson@topquadrant.com>
wrote:

> Hello Mark,
>
> QUDT is now a non-profit organization with the desire to join W3C to move
> forward on standardization. The management at NASA has given its approval
> for QUDT to proceed with this.
>
> Release 2 is a substantial body of work that is finally reaching a
> publication status. This involves the generation of content with support
> for LaTeX formatting. Examples can be seen at the following web pages:
>
>
>    1. The documentation on the QUDT schema -
>    http://www.linkedmodel.org/doc/2015/DOC_schema-qudt-v2.0
>    2. An example of a LaTeX rendered instance of the Hartree Unit -
>    http://www.linkedmodel.org/doc/2015/hartree
>
> The site www.linkedmodel.org has links to documentation for other
> ontologies and for those that QUDT depends on (VAEM, VOAG and DTYPE).
>
> All the QUDT ontologies are managed on a GitHub site. There is also a
> WordPress site.
>
> QUDT would welcome participation from others and once we become a member
> of W3C a working group would be important to establish. Perhaps we should
> have a discussion on how to get started?
>
> We have long believed that for (some) data to be truly linkable on the web
> it benefits from being quantified.
>
> I will send another email setting out the remaining work we are doing on
> the ontologies. In my view the most important of which is standardization
> of the QNames of the units (e.g, unit:SEC for second, unit:S for Siemen,
> and unit:KM-PER-SEC not unit:KM-PER-S) so that they are consistently
> reference-able and conforms with their standard abbreviations . This work
> is almost complete for SI units.
>
> Regards,
>
>
> Ralph Hodgson, @ralphtq <http://twitter.com/ralphtq>
>
> TopQuadrant, Inc., www.topquadrant.com @TopQuadrant
> <http://twitter.com/topquadrant>
> *cell: +1 781-789-1664 <%2B1%20781-789-1664> / fax: 703 299-8330
> <703%20299-8330> / main: 919 300-7945 <919%20300-7945>*
>
>
> On May 7, 2015, at 4:56 AM, Mark Harrison <mark.harrison@cantab.net>
> wrote:
>
> Dear Martin,
>
> I understand your very valid concerns about Linked Data resources that are
> not supported and maintained and end us wasting time for developers.
> However, from this thread it also seems that there is quite some interest
> in having a well recognised ontology for units of measure in which units
> have corresponding stable URIs that link to definitions, UN ECE codes,
> conversion factors and offsets, etc.  QUDT 1.1 made a very good start on
> this, although it had one or two inaccurate cross-references.  For example,
> I found within http://qudt.org/vocab/unit#Grain the following nonsensical
> triple:
>
> <http://qudt.org/vocab/unit#Grain>  skos:exactMatch  <
> http://dbpedia.org/resource/Cereal> .
>
> There are some other gaps in QUDT 1.1, such as missing resources for units
> such as milligram, microgram - and because the SI base unit of mass is the
> kilogram, it is not sufficient to simply define the multipliers such as
> 'milli', 'micro', because we don't usually talk about milligrams as
> microkilograms, for example.
>
> Having said that, if QUDT 1.1 were updated, corrected, supported a more
> complete set of units and provided cross-references to the corresponding UN
> ECE Common Code values as strings, I think it (or something very like it)
> could be an extremely valuable resource for everyone, especially because of
> the conversion factors and offsets.
>
> The QUDT.org website appears to be last updated in March 2014 and there
> is some information and a presentation by Ralph Hodgson (copied) about the
> plans for release 2.0 of QUDT.  However, I'm not sure whether that work has
> stalled or is under-resourced or is spending a long time in careful
> internal review.  Maybe those of us who are interested in making this
> happen could offer to share the workload and accelerate the progress.  In
> case NASA / TopQuadrant is no longer the place to host it, then perhaps we
> could reasonably ask W3C to host it in perpetuity and maintain a liaison
> with the UN, ISO and other relevant bodies to ensure that we're aware of
> their changes that should be reflected through maintenance updates to such
> a vocabulary.
>
> We're soon hoping to see much more structured data about products being
> published openly on the web as linked data, potentially including details
> about ingredients, nutrition and allergens.  GS1 has already prepared begun
> drafting a web vocabulary [ see http://www.gs1.org/gtin_plus_public_review
> ] to help manufacturers and retailers express such information in much
> richer detail than they can currently using schema.org alone - and
> efforts are underway to harmonise this effort with schema.org to make
> life easier for developers.  I expect that a stable supported ontology with
> URIs and Linked Data for units of measure along the lines of a QUDT 2.0
> could be far more useful to software developers than simply denoting a unit
> of measure by its UN ECE Common Code string.  We can certainly do better
> than that.  It could almost certainly avoid a large amount of duplicated
> effort in coding conversion factors and offsets and would also help to
> ensure that whether the product specifications are provided in SI units or
> non-SI units (as they are in different regions of the world), the same
> quantitative information is readily available so software applications,
> without ambiguity or unnecessary duplication of effort by developers.
>
> I hope that Ralph Hodgson can chime in with a brief status update on QUDT
> 2.0 - and also that those of us who would be interested in helping to
> accelerate this (or something similar) can step forward and offer to help
> with reviewing it or beta testing it - or filling in the gaps for the
> missing features.
>
> Best wishes,
>
> - Mark Harrison
>
>
>
>
> On 7 May 2015, at 09:08, martin.hepp@ebusiness-unibw.org wrote:
>
> Dear Kingsley:
> Technically, as we agree, this is no big deal.
>
> But there are so many abandoned RDF / Semantic Web efforts rottening on
> the Web and wasting the time of developers who try to built something on
> top of it -- until they find out that the project is way out of date --
> that I do not see any gain in such a quick fix.
>
> Martin
>
>
> On 07 May 2015, at 01:25, Kingsley Idehen <kidehen@openlinksw.com> wrote:
>
> On 5/6/15 6:31 PM, martin.hepp@ebusiness-unibw.org wrote:
>
> The problem is not the one time generation. The problems are as follows:
>
> 1. Copyright - Are you allowed to republish the code set as RDF?
> 2. Sustainability - Are you commited to keep the URIs dereferencable, or
> will some domain grabber take the domain name once the creator has
> completed his/her PhD and lost interest.
> 3. Updates - Will you keep the RDF version in sync whenever the standard
> changes?
>
> Unless there is a clear "yes" to all three questions, it is better to use
> the official codes than derived URIs.
>
> Martin
>
>
> Martin,
>
> What's wrong with:
>
> <#someResolvableVariantOfIdentifier>
> a owl:Thing ;
> dcterms:identifier "{literal-variant-of-standard-identifier}" .
>
> Which can be further embellished by Linked Data publisher in their
> ontology/vocabulary by adding the following:
>
> dcterms:identifier
> a owl:InverseFunctionalProperty .
>
> Productive workflow:
>
> 1. Get the data dump in a spreadsheet
> 2. Save as CSV
> 3. Load into LOD or Google Refine
> 4. Map to relevant ontology (existing, or new)
> 5. Dump data into an RDF document
> 6. Publish (note: using # as indexical mechanism makes the publication
> Linked Open Data prinicples compliant off-the bat).
>
>
> It can be done quite easily. I deliberatly opted not to do it :)
>
>
> Kingsley
>
>
>
>
> On 06 May 2015, at 23:56, Wes Turner <wes.turner@gmail.com> wrote:
>
> How much time do you think it would take to generate RDF (and namespaced
> URIs) from the linked spreadsheet?
>
> Mappings to/from UN/CEFACT codes (as owl:sameAs mappings to strings) could
> certainly be useful.
>
> On May 6, 2015 4:31 PM, "martin.hepp@ebusiness-unibw.org" <
> martin.hepp@ebusiness-unibw.org> wrote:
> I think a validator should simply use the list of valid codes from the
> most recent UN/CEFACT document (available as MS Excel from
> http://www.unece.org/cefact/codesfortrade/codes_index.html).
>
> There might be unit of measurement ontologies out there that hold the
> UN/CEFACT Common Code string for a subset of all units as a literal value.
> But for validation, one should use the authoritative list from the Excel
> files (since they are updated from time to time).
>
> URIs are not better than strings for validation, because URIs are strings.
>
> Best wishes / Mit freundlichen Grüßen
>
> Martin Hepp
>
> -------------------------------------------------------
> martin hepp
> e-business & web science research group
> universitaet der bundeswehr muenchen
>
> e-mail:  martin.hepp@unibw.de
> phone:   +49-(0)89-6004-4217
> fax:     +49-(0)89-6004-4620
> www:     http://www.unibw.de/ebusiness/ (group)
>        http://www.heppnetz.de/ (personal)
> skype:   mfhepp
> twitter: mfhepp
>
> Check out GoodRelations for E-Commerce on the Web of Linked Data!
> =================================================================
> * Project Main Page: http://purl.org/goodrelations/
>
>
>
>
> On 06 May 2015, at 20:34, Wes Turner <wes.turner@gmail.com> wrote:
>
> Thanks!
>
> I notice that with QUDT there are SI conversion factors and complete URIs
> for each unit.
>
> Is there a schema for validation of "schema:QuantativeValues supports all
> UN/CEFACT Common Codes"?
>
> (A similar quandry as with MedicalCode; where URI namespaces (like icd10:)
> would be more helpful for terminological validation and disambiguation than
> plain string keys)
>
> On May 6, 2015 4:26 AM, "martin.hepp@ebusiness-unibw.org" <
> martin.hepp@ebusiness-unibw.org> wrote:
>
> Hi Wes,
> sorry for a very late reply:
>
> Actually you could easily use schema:QuantitativeValue for both time and
> volume, with SEC as the unit code for t and LTR as the unit code for
> liters, and link both via schema:valueReference, or better, and
> owl:subProperty thereof.
>
> For the principle, see
>
>
> http://wiki.goodrelations-vocabulary.org/Documentation/Structured_values_and_value_references
>
>
> schema:QuantativeValues supports all UN/CEFACT Common Codes for units,
> which should cover all you need:
>
>
>
> http://wiki.goodrelations-vocabulary.org/Documentation/UN/CEFACT_Common_Codes
>
> (Mind the full list in the public Excel files, the page just highlights a
> small subset.)
>
> Best wishes / Mit freundlichen Grüßen
>
> Martin Hepp
>
> -------------------------------------------------------
> martin hepp
> e-business & web science research group
> universitaet der bundeswehr muenchen
>
> e-mail:  martin.hepp@unibw.de
> phone:   +49-(0)89-6004-4217
> fax:     +49-(0)89-6004-4620
> www:     http://www.unibw.de/ebusiness/ (group)
>        http://www.heppnetz.de/ (personal)
> skype:   mfhepp
> twitter: mfhepp
>
> Check out GoodRelations for E-Commerce on the Web of Linked Data!
> =================================================================
> * Project Main Page: http://purl.org/goodrelations/
>
>
>
>
> On 01 May 2015, at 13:45, ☮ elf Pavlik ☮ <perpetual-tripper@wwelves.org>
> wrote:
>
> Hi Wes,
>
> On 01/26/2014 07:20 AM, Wes Turner wrote:
>
> Say I am trying to share a tabular dataset. [1] There's metadata for
> the Dataset, and there's metadata for the particular columns (which
> applies to the particular data items).
>
> For example:
>
> t   volume (liters)
> -----------------
> 1  1
> 2  0.7
> 3  0.5
> 4  0.3
> 5  0.1
>
> Questions
> ===========
> # Is there (a good) way to specify these units and quantities (in
> addition to XSD datatypes)?
>
> You might like to check out
> * https://iotdb.org/pub/iot-unit.html
>
> Cheers!
>
>
>
>
>
>
> --
> Regards,
>
> Kingsley Idehen
> Founder & CEO
> OpenLink Software
> Company Web: http://www.openlinksw.com
> Personal Weblog 1: http://kidehen.blogspot.com
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> Personal WebID: http://kingsley.idehen.net/dataspace/person/kidehen#this
>
>
>
>
>
>
>


-- 
Wes Turner
https://westurner.org
https://wrdrd.com/docs/consulting/knowledge-engineering