[esip-semanticweb] help with marking up WMS/WCS Capability docs?

[John Graybeal]

I am not deep in any one of these details, but I am a little familiar  
with all the possibilities you mention. So consider the following as  
notions to be verified:

1) RDFa won't fit gracefully into the OGC schema as written, because  
it is using a different set of elements (that is, it is tuned to the  
HTML elements). "To date, because XHTML is extensible while HTML is  
not, RDFa has only been specified for XHTML 1.1." [1]  The way it  
works is to add attributes, which must be in an RDFa-compatible XHTML  
schema if the document is to validate.

2) I wholeheartedly endorse the intent to use controlled vocabularies  
in a way that is compatible with the semantic web. All that should be  
necessary to do this is to find a suitable place where a URI can be  
placed.  Then you can create controlled vocabularies whose terms  
correspond to URIs. There is extensive guidance on this topic at the  
MMI site [2].  I do not know of any reason these approaches would be  
incompatible with the ESIP ontologies.

3) The way OOSTethys [1] chose to add more specific descriptions/ 
references to SensorML/O&M was through the use of xlink, which is  
supported in the OGC schema. Examples are on the OOSTethys site. As  
far as I know, this is the most used OGC practice to meet this need to  
date. (Because I don't know of any other particular recommendation.)   
Note that if a standard allows a name to be specified as a URI (which  
most of the SWE standards do, yes?), that is another place where the  
sensor web.

4) If your keywords are to be applied document-wide, and they are  
about fairly broad concepts, there is a pretty good chance that the  
Dublin Core metadata[4] has a field into which URIs can be placed. I  
don't know what flexibility there is for specifying document metadata  
at the head of WMS/WCS though.  But I would encourage this approach  
if  you want to describe the whole document, rather than any  
particular part of it.

John


[1] http://www.w3.org/TR/xhtml-rdfa-primer/#id84480
[2] MMI Guides re vocabularies and semantic web: http://marinemetadata.org/guides/vocabs
[3] OOSTethys: http://www.oostethys.org
[4] Dublin Core elements list: http://dublincore.org/documents/dces/


On Jul 15, 2009, at 12:53 PM, Christopher Lynnes wrote:

> Greetings!
>
> Over in the Air Quality Cluster, we are experimenting with using  
> some kind of structured markup / tagging of OGC WMS and WCS  
> capabilities documents (inside <Keyword> elements) to allow us to do  
> structured searches on the documents.  An example might be, "give me  
> the layers where Dataset = 'OMI_AI_G'". Seehttp://wiki.esipfed.org/index.php/WMS_GetCapabilities#WMS_GetCapabilities_Layer_Description
>
> Thing is, we figure if we are going to try to implement this kind of  
> markup with a quasi-controlled vocabulary, we should do it in such a  
> way that it is compatible with or even leverages the semantic web.   
> We have pondered a machine tags approach, e.g.,  
> <Keyword>esip:dataset=OMI_AI_G</Keyword>.  (A link to an initial  
> attempt of a WMS that includes the current keyword encoding: http://webapps.datafed.net/AIRNOW.ogc?service=wms&request=getCapabilities&version=1.1.1) 
> .
>
> Alternatively, we have heard RDFa mentioned for microformats, though  
> mostly in the context of XHTML.  Can this be applied to OGC's XML  
> and if so, how?
>
> Can the ESIP Semantic Web cluster provide a recommendation or  
> suggestion in how to move forward that would be:
> (a) flexible and extensible,
> (b) compatible with the evolving ESIP datatype and services ontology  
> and
> (c) lightweight and easy to use?
> --
> Christopher Lynnes             NASA/GSFC, Code 610.2          
> 301-614-5185
>
> _______________________________________________
> esip-semanticweb mailing list
> esip-semanticweb at rtpnet.org
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John

--------------
John Graybeal   <mailto:graybeal at mbari.org>  -- 831-775-1956
Monterey Bay Aquarium Research Institute
Marine Metadata Interoperability Project: http://marinemetadata.org