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Re: [SUMMARY] QuantitativeValue / Units of Measure - Proposal

From: Alex Milowski <alex@milowski.com>
Date: Fri, 16 Aug 2013 13:49:15 -0700
Message-ID: <CABp3FNJhEntqd2L8_HX+vMJvNj1vgobmj4qkdcz2OgxpBiyMOA@mail.gmail.com>
To: "public-vocabs@w3.org" <public-vocabs@w3.org>
Hmm ... not a single reply of feedback on this since June.

Does that mean:

A. people aren't interested,
B. not interested at this time,
C. wait, what?
D. you're off your rocker.

?



On Thu, Jun 6, 2013 at 2:21 PM, Alex Milowski <alex@milowski.com> wrote:

> I went through the schemas and found the uses of
> http://schema.org/QuantitativeValue:
>
> Time Duration:
>
> http://schema.org/advanceBookingRequirement
> http://schema.org/deliveryLeadTime
> http://schema.org/durationOfWarranty
> http://schema.org/eligibleDuration
>
> Dimensions / weight
>
> http://schema.org/depth
> http://schema.org/height
> http://schema.org/weight
> http://schema.org/width
>
> Counts (possibly unit less?)
>
> http://schema.org/eligibleQuantity
> http://schema.org/inventoryLevel
>
> Having some familiarity with the UN/CEFACT efforts, I also went through
> their unit codes and I find them troubling for general use:
>
>   1. XML Schema's durations aren't possible.  A great deal of effort went
> into making a value space and lexical representation that is based on ISO
> time standards (ISO 8601).
>
>   2. The codes are odd for common use (e.g. Hour = HUR, instead of 'H' or
> 'h', ANN = year, instead of 'yr' or 'Y', GRM = gram, instead of 'g')
>
>   3. There are very general properties of depth, heigh, width, and weight
> for which I could expect to use outside of UN/CEFACT contexts.
>
> That said, I do think it makes sense to have a "unit code" property for
> contexts where UN/CEFACT information is being described.  That property
> should never be used for other purposes because of the broad nature of
> these codes and the fact that a random two or three letter code could mean
> something (e.g. 11 = outfit).
>
> On the other hand, if I want to describe the weight of an object using SI
> units, I need a way to say that with a different property.  That is, I
> should be able to use the standard prefixing scheme of SI units to say
> "kg", "g" "mg" and so on without having to resort to looking up a strange
> code.
>
> If you look at Wikipedia's entry on SI units [1] or  QUDT [2], you'll see
> the consistent terminology for a unit abbreviation is "symbol".  Since we
> have one namespace, "symbol" alone has far too many interpretations and so
> "unitSymbol" might be better.
>
> As mentioned before, grounding a unit by some well defined concept is a
> really good idea and URI is seems the best option because it will integrate
> well with QUDT.
>
> Proposal:
>
> Add two properties to QuantitativeValue: one for the unit symbol and one
> for the unit's "reference URI":
>
>     http://schema.org/unitSymbol - the unit symbol, a string value
>     http://schema.org/unit - the URI of the unit's definition (e.g. QUDT
> unit:Gram, expanded)
>
> and this allows:
>
>     <p typeof="QuantitativeValue">
>         <span property="value">10</span><span
> property="unitSymbol">g</span>
>     </p>
>
> and alternatively, for more specificity:
>
>     <p property="weight" typeof="QuantitativeValue">
>         <span property="value">10</span><span
> property="unitSymbol">g</span><span property="unit" resource="unit:Gram"/>
>     </p>
>
> or
>
>    <p property="weight" typeof="QuantitativeValue">
>        <span property="value">10</span><span property="unitSymbol"><span
> property="unit" resource="unit:Gram">g</span></span>
>    </p>
>
> [1] http://en.wikipedia.org/wiki/International_System_of_Units
> [2] http://www.qudt.org/
>
> --
> --Alex Milowski
> "The excellence of grammar as a guide is proportional to the paucity of the
> inflexions, i.e. to the degree of analysis effected by the language
> considered."
>
> Bertrand Russell in a footnote of Principles of Mathematics
>



-- 
--Alex Milowski
"The excellence of grammar as a guide is proportional to the paucity of the
inflexions, i.e. to the degree of analysis effected by the language
considered."

Bertrand Russell in a footnote of Principles of Mathematics
Received on Friday, 16 August 2013 20:49:43 UTC

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