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Ethan,

Maybe I'm being daft in missing it, but could I ask about more details 
in the richer metadata model? My hunch is that, depending on the details 
of the information you want to bring in, there might be more precise 
alternatives to what's in SKOS. Are you aiming to have a link between a 
skos:Concept and texts/documents related to that concept?

Patrick

On 02/11/2012 03:14 PM, Ethan Gruber wrote:
> Hi Ross,
>
> Thanks for the input.  My main objective is to make the richer metadata
> available one way or another to people using our web services.  Do you
> think it makes more sense to link to a URI of the richer metadata document
> as skos:related (or similar)?  I've seen two uses for skos:related--one to
> point to related skos:concepts, the other to point to web resources
> associated with that concept, e.g., a wikipedia article.  I have a feeling
> the latter is incorrect, at least according to the documentation I've read
> on the w3c.  For what it's worth, VIAF uses owl:sameAs/@rdf:resource to
> point to dbpedia and other web resources.
>
> Thanks,
> Ethan
>
> On Sat, Feb 11, 2012 at 12:21 PM, Ross Singer<[log in to unmask]>  wrote:
>
>> On Fri, Feb 10, 2012 at 11:51 PM, Ethan Gruber<[log in to unmask]>  wrote:
>>> Hi Ross,
>>>
>>> No, the richer ontology is not an RDF vocabulary, but it adheres to
>> linked
>>> data concepts.
>> Hmm, ok.  That doesn't necessarily mean it will work in RDF.
>>> I'm looking to do something like this example of embedding mods in rdf:
>>>
>> http://www.daisy.org/zw/ZedAI_Meta_Data_-_MODS_Recommendation#RDF.2FXML_2
>> Yeah, I'll be honest, that looks terrible to me.  This looks, to me,
>> like kind of a misunderstanding of RDF and RDF/XML.
>>
>> Regardless, this would make useless RDF (see below).  One of the hard
>> things to understand about RDF, especially when you're coming at it
>> from XML (and, by association, RDF/XML) is that RDF isn't
>> hierarchical, it's a graph.  This is one of the reasons that the XML
>> serialization is so awkward: it looks something familiar XML people,
>> but it doesn't work well with their tools (XPath, for example) despite
>> the fact that it, you know, should.  It's equally frustrating for RDF
>> people because it's really verbose and its syntax can come in a
>> million variations (more on that later in the email) making it
>> excruciatingly hard to parse.
>>
>>> These semantic ontologies are so flexible, it seems like I *can* do
>>> anything, so I'm left wondering what I *should* do--what makes the most
>>> sense, semantically.  Is it possible to nest rdf:Description into the
>>> skos:Concept of my previous example, and then place<nuds:nuds>.....more
>>> sophistated model......</nuds:nuds>  into rdf:Description (or
>> alternatively,
>>> set rdf:Description/@rdf:resource to the URI of the web-accessible XML
>> file?
>>> Most RDF examples I've looked at online either have skos:Concept or
>>> rdf:Description, not both, either at the same context in rdf:RDF or one
>>> nested inside the other.
>>>
>> So, this is a little tough to explain via email, I think.  This is
>> what I was referring to earlier about the myriad ways to render RDF in
>> XML.
>>
>> In short, using:
>> <skos:Concept about="http://example.org/foo">
>>   <skos:prefLabel>Something</skos:prefLabel>
>>   ...
>> </skos:Concept>
>>
>> is shorthand for:
>>
>> <rdf:Description about="http://example.org/foo">
>>   <rdf:type resource="http://www.w3.org/2004/02/skos/core#Concept" />
>>   <skos:prefLabel>Something</skos:prefLabel>
>> </rdf:Description>
>>
>> So, yeah, you use one or the other.
>>
>> That said, I'm not sure your ontology is really going to work well,
>> you'll just have to try it.  One thing that would probably be useful
>> would be to serialize out a document with your nuds vocabulary as
>> rdf/xml and then use something like rapper (comes with the redland
>> libraries) to convert it to something more RDF-friendly, like turtle,
>> and see if it makes any sense.
>>
>> For example, your daisy example above:
>>
>> <rdf:RDF
>>                 xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
>>                 xml:mods="http://www.daisy.org/RDF/MODS">
>>
>>                 <rdf:Description rdf:ID="daisy-dtbook2005-exemplar-01">
>>
>>                         <mods:titleInfo>
>>                                 <mods:title>World Cultures and
>> Geography</mods:title>
>>                         </mods:titleInfo>
>>
>>                         <mods:name>
>>                                 <mods:namePart>Sarah Witham
>> Bednarz</mods:namePart>
>>                                 <mods:role>
>>                                         <mods:roleTerm
>> mods:type="text">author</mods:roleTerm>
>>                                 </mods:role>
>>                         </mods:name>
>>
>>                         <mods:name>
>>                                 <mods:namePart>Inés M.
>> Miyares</mods:namePart>
>>                                 <mods:role>
>>                                         <mods:roleTerm
>> mods:type="text">author</mods:roleTerm>
>>                                 </mods:role>
>>                         </mods:name>
>>
>>                         <mods:name>
>>                                 <mods:namePart>Mark C. Schug</mods:namePart>
>>                                 <mods:role>
>>                                         <mods:roleTerm
>> mods:type="text">author</mods:roleTerm>
>>                                 </mods:role>
>>                         </mods:name>
>>
>>                         <mods:name>
>>                                 <mods:namePart>Charles S.
>> White</mods:namePart>
>>                                 <mods:role>
>>                                         <mods:roleTerm
>> mods:type="text">author</mods:roleTerm>
>>                                 </mods:role>
>>                         </mods:name>
>>
>>                         <mods:originInfo>
>>                                 <mods:publisher>DAISY
>> Consortium</mods:publisher>
>>
>>   <mods:dateCreated>2005-01-14</mods:dateCreated>
>>                                 <mods:version>3</mods:version>
>>
>>   <mods:dateModified>2005-07-27</mods:dateModified>
>>                         </mods:originInfo>
>>
>>                         <mods:relatedItem mods:type="original">
>>                                 <mods:originInfo>
>>                                         <mods:publisher>McDougal
>> Littell</mods:publisher>
>>                                         <mods:place>Evanston,
>> Illinois</mods:place>
>>
>>   <mods:dateCreated>2003</mods:dateCreated>
>>                                 <mods:originInfo>
>>                         </mods:relatedItem>
>>
>>                         <mods:identifier
>> mods:type="isbn10">0618168419</mods:identifier>
>>
>>                         <mods:typeOfResource>text</mods:typeOfResource>
>>
>>                         <mods:physicalDescription>
>>                                 <mods:form>Hardcover print</mods:form>
>>                         </mods:physicalDescription>
>>
>>                         <mods:subject>Geography</mods:subject>
>>
>>                         <mods:language>en</mods:language>
>>
>>                         <mods:note mods:type="description">Culture and
>> geography textbook
>> for highschool</mods:note>
>>
>>                 <rdf:Description>
>>
>>         </rdf:RDF>
>>
>> rapper turns this into:
>>
>> <file:///home/ross/tmp/daisy.xml#daisy-dtbook2005-exemplar-01>
>>     mods:titleInfo [
>>         a mods:title
>>     ] .
>>
>> []
>>     a mods:namePart .
>>
>> which is not terribly useful.
>>
>> I guess what I'm saying is that RDF/XML isn't really intended to be
>> used as XML nor is it terribly useful in that capacity because
>> 'native' XML-based schemas are, by definition, hierarchical (plus they
>> aren't constrained by the E-A-V model).  RDF/XML is really just a
>> standardized way to share RDF graphs (the first and now most maligned
>> way, really) that happened to use XML because there was plumbing for
>> XML there already (parsers, mime-types, etc.), but it shouldn't really
>> be mistaken for 'XML'.
>>
>> Try your data in rapper and see if your resources model correctly,
>> otherwise I would suggest making a custom vocabulary based on your
>> ontology that conforms better to RDFS or OWL.
>>
>> Good luck,
>> -Ross.
>>> Thanks,
>>> Ethan
>>>
>>> On Fri, Feb 10, 2012 at 9:44 PM, Ross Singer<[log in to unmask]>
>> wrote:
>>>> The whole advantage of RDF is that you can pull properties from
>> different
>>>> vocabularies (as long as they're not logically disjoint). So, assuming
>> your
>>>> richer ontology is some kind of RDF vocabulary, this exactly *what* you
>>>> should be doing.
>>>>
>>>> -Ross.
>>>>
>>>> On Feb 10, 2012, at 4:31 PM, Ethan Gruber<[log in to unmask]>  wrote:
>>>>
>>>>> Hi all,
>>>>>
>>>>> I'm working on an RDF model for describing concepts.  I have
>> skos:Concept
>>>>> nested inside rdf:RDF.  Most documents will have little more than
>> labels
>>>>> and related links inside of skos:Concept.  However, for a certain
>> type of
>>>>> concept, we have XML documents with a more sophisticated ontology and
>>>>> structure for describing the concept.  I could embed this metadata
>> into
>>>> the
>>>>> RDF or reference it as an rdf:resource.  It doesn't matter much to me
>>>>> either way, but I'm unsure of the semantically correct way to create
>> this
>>>>> model.
>>>>>
>>>>> Suppose I have:
>>>>>
>>>>> <rdf:RDF>
>>>>> <skos:Concept rdf:about="URI">
>>>>> <skos:prefLabel xml:lang="en">Label</skos:prefLabel>
>>>>> <nuds:nuds>.....more sophistated model......</nuds:nuds>
>>>>> </skos:Concept>
>>>>> </rdf:RDF>
>>>>>
>>>>> Is it okay to have the more sophistated metadata model embedded in
>>>>> skos:Concept alongside labels and related links?  Suppose I want to
>> store
>>>>> the more sophisticated metadata separately and reference it?  I'm not
>>>> sure
>>>>> what property adequately addresses this relation, semantically.
>>>>>
>>>>> Recommendations?
>>>>>
>>>>> Thanks,
>>>>> Ethan