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Ivan,

Thanks for the update. I'm in the early stages of formulating a 
comparison between the W3C work and the DCMI work (to date). My first 
impression is that the DCMI work has a focus on documentation, and the 
W3C work primarily sets up structures for validation. In the end, we may 
have enough overlap that it would make sense to combine the efforts. I 
hope that someone from the W3C community will be able to follow the DCMI 
group. And vice versa, of course.

I'll alert you as soon as there's something visible on the wiki.

kc

On 6/9/14, 11:33 AM, Ivan Herman wrote:
> Just an additional information: I would expect an official charter proposal for a W3C group to go out relatively soon (I think it will be called "Data Shape"), meaning that a corresponding WG may start its work in autumn. Which technique (shape language, modified OWL semantics, or other) will be used is of course not decided at this point, it will be a decision of the group.
>
> Cheers
>
> Ivan
>
> On 09 Jun 2014, at 02:46 , Karen Coyle <[log in to unmask]> wrote:
>
>> Yes, if you look at the W3C validation workshop I cited, much of the validation is done with SPARQL, with or without OWL. Using the closed world method may work in some cases, but it depends greatly on the nature of your closed and open worlds. What the Dublin Core AP work promotes is being very careful that your closed world validation needs do not affect your open world semantics. In other words, if you define your ontology with OWL constraints that you wish to interpret in a closed world, beware that those same constraints, with a different, open world context, apply to your data universally. This may not yield the desired results in the open world. (Note that many of the examples in the W3C workshop were enterprise uses of RDF, thus not terribly concerned with open world semantics. I think we have a special case with bibliographic data because not only do we want it to be open, but our data is, in essence, massively crowd-sourced, and not at all under a single point of control
 .
)
>>
>> In addition, there are many aspects of application profiles that are not part of the RDF concept. APs can define what LOV [1] calls a "vocabulary" -- that is, a set of classes and properties that are used in a particular data set.
>>
>> In any case, if anyone wishes to participate, there is a new DCMI task group that over the next year will look into the needs for application profiles for metadata in RDF.[2]  It is just beginning, and anyone can join in. Discussion will take place on the dc-architecture [3] mailing list. If you have use cases to contribute, please send them to the list.
>>
>> kc
>>
>> [1] http://lov.okfn.org/dataset/lov/
>> [2] http://wiki.dublincore.org/index.php/RDF-Application-Profiles
>> [3] https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=dc-architecture&A=1
>>
>> On 6/8/14, 9:31 PM, [log in to unmask] wrote:
>>> Perhaps we do not "constrain" in the usual data processing sense, but useful information can be mechanically derived using these technologies.
>>>
>>> If I apply some ontology to a knowledge base and do not thereafter discover a certain resource X categorized into a certain type T, I normally interpret that in an open world as meaning that I just don't yet know whether X is a T. But, for my own convenience and within the privacy of my own systems, I _can choose_ to interpret that absence to myself to mean that X is not a T, as long as I don't publish this assertion or any assertions derived therefrom. It doesn't seem reasonable to me to ignore this possibility for workflow.
>>>
>>> It is also very possible to reinterpret OWL with formal closed-world semantics: Clark & Parsia offer a nice example at: http://docs.stardog.com/icv/icv-specification.html
>>>
>>> ---
>>> A. Soroka
>>> The University of Virginia Library
>>>
>>> On Jun 7, 2014, at 4:58 PM, Karen Coyle <[log in to unmask]> wrote:
>>>
>>>> There is, however, a bit of a problem with writing profiles and their constraints in RDF -- which is that RDF (and OWL) support inferences, but not constraints in the usual data processing sense. If you've looked into the W3C validation work, or the DCMI AP work, you see that there are points where one either bends the RDF rules, or moves into another language with different semantics.
>>>>
>>>> W3C validation: http://www.w3.org/2012/12/rdf-val/
>>>> DCMI RDF APs: http://wiki.dublincore.org/index.php/RDF-Application-Profiles
>>>> Shape Expressions: http://www.w3.org/2013/ShEx/Primer
>>>>
>>>> The DCMI group is going to be looking into APs from the DCMI point of view. I'm personally not sure what this is going to require, but in trying to think through how it might be defined in RDF, I run into problems, especially with cardinality and anything requiring structure.
>>>>
>>>> kc
>>>>
>>>> On 6/7/14, 7:14 PM, [log in to unmask] wrote:
>>>>> I have just learned about the Bibframe Profiles.
>>>>>
>>>>> Since Bibframe is based on RDF, why are Bibframe Profiles not based on RDF?
>>>>>
>>>>> As I understand, the constraints described in Bibframe Profiles are constraints on RDF elements and vocabularies, and do not constrain mere data. I'm not sure about what is meant with "structural constraints", maybe also integrity constraints?
>>>>>
>>>>> So expressing Bibframe Profiles in RDF as rules would be more beneficial to the semantic web community.  I think it is possible to express the rules as an ontology. By doing this, informal notations or plain JSON or EBNF notations would no longer be necessary to express a Bibframe Profile, the document could be rewritten to use RDF (serialized in Turtle, JSON-LD, etc. whatever is convenient)
>>>>>
>>>>> Best,
>>>>>
>>>>> Jörg
>>>>
>>>> --
>>>> Karen Coyle
>>>> [log in to unmask] http://kcoyle.net
>>>> m: 1-510-435-8234
>>>> skype: kcoylenet
>>>
>>
>> --
>> Karen Coyle
>>
>> [log in to unmask] http://kcoyle.net
>>
>> m: 1-510-435-8234
>> skype: kcoylenet
>>
>
>
> ----
> Ivan Herman
> 4, rue Beauvallon, clos St Joseph
> 13090 Aix-en-Provence, France
> GPG: 0x343F1A3D
> http://www.ivan-herman.net
>
>
>
>
>

-- 
Karen Coyle
[log in to unmask] http://kcoyle.net
m: 1-510-435-8234
skype: kcoylenet