Re: Disambiguating Things

I suspect you'll find this gets complex quite quickly as you run into
https://en.wikipedia.org/wiki/Functional_Requirements_for_Bibliographic_Records
-like distinctions.

Back in the FOAF project we experimented with a sha1sum property. It turns
out two entirely different entities (on one conceptualization) can have the
same character/byte content and hence hash.

e.g. in a unix-y environment:

touch hello_world.txt

shasum hello_world.txt


... gives something like -rw-rw-r-- 1 ubuntu ubuntu 0 Jul  3 15:21
hello_world.txt

shasum hello_world.txt

da39a3ee5e6b4b0d3255bfef95601890afd80709  hello_world.txt

... on a different machine you'll have a different datestamp and username
but the same empty file. Various parts of schema.org have some approach to
describing these kinds of distinction for CreativeWorks (e.g.
"workExample"; or "encoding" on MediaObject; or "distribution" vs
"contentUrl" on Dataset -> DataDownload, ...). And the further you get from
bytes, the more tenuous the link back to checksum maths; c.f.
dnaChecksum...).

I can see value in having enough clarity around MediaObject and nearby that
we can talk about checksums more cleanly, but I'm not sure how far that'll
get us. It would be interesting for datasets and software applications and
so on to have this capability, so that you can look up the right metadata
to go with a concrete download / media file. Do you have some more examples
we can work through?

cheers,

Dan

On 3 July 2017 at 16:32, Thad Guidry <thadguidry@gmail.com> wrote:

> I now have the need to disambiguate between Things at a deeper level than
> just property comparisons.
>
> I'd like to see the use or way of telling my apps that a checksum is the
> disambiguatingDescription or identifier property on my Things.
>
> Currently, we have no Type of "Checksum" under Intangible.  That might be
> thoughtful in the future.
>
> But we do have PropertyValue available, but it loses the
>
> This need arouse from the recent introduction of "checksum" property in
> Wikidata as well...hence my Apps can take advantage of that now but not
> without Schema.org uplifts, since my Apps depend on valid properties in
> Schema.org... (insert skunkworks stuff here)
>
> I guess this is an alternative way to perform what I am needing
>
> {
>   "@context": "http://schema.org/",
>   "@type": "Thing",
>   "name": "Some IoT Thing",
>   "url": "http://www.example.com/Some+IoT+Thing",
>   "identifier": {
>     "@type": "PropertyValue",
>     "alternateName":"checksum",
>     "additionalType":"https://www.wikidata.org/wiki/Q218341",
>     "value": "8044d756b7f00b695ab8dce07dce43e5",
>     "unitCode":"https://www.wikidata.org/wiki/Q185235"
>     }
> }
>
> Thoughts or ideas or any;thing that I am missing ?
>
> If the above is actually a really good example, then we should probably
> add it as an 3rd example on http://schema.org/identifier  ?
>
> -Thad
> +ThadGuidry <https://www.google.com/+ThadGuidry>
>
>