- From: Seaborne, Andy <Andy_Seaborne@hplb.hpl.hp.com>
- Date: Mon, 7 Apr 2003 14:50:52 +0100
- To: "'Kevin Smathers'" <ks@micky.hpl.hp.com>
- Cc: "'www-rdf-dspace@w3.org'" <www-rdf-dspace@w3.org>
> -----Original Message----- > From: Kevin Smathers [mailto:ks@micky.hpl.hp.com] > Sent: 5 April 2003 00:44 > To: Seaborne, Andy > Cc: 'www-rdf-dspace@w3.org' > Subject: Re: SIMILE Research Drivers > > > Hi Andy, > > Mick and I have been working on describing a demonstrator > which brings out some of the issues surrounding distribution (I've > been describing the distribution problem from Genesis' perspective, > and Mick has been translating into Simile's application domain.) Great. > > On Fri, Apr 04, 2003 at 02:45:07PM +0100, Seaborne, Andy wrote: [...] > > The Semantic Web isn't a number of closed worlds so > information from > > SIMILE will be reused by other systems, whether portals, client-end > > applications or something else. The current document covers this. > > The other way round is also interesting - how does SIMILE > use semantic > > web information from elsewhere? Library information can be > ingested > > but what about dynamic information? > > > > Examples: schedules related to course material. Other papers in the > > same track or same session at a conference. > > I think that the demo will address this. The mechanism used > for sharing of external metadata should be similar to the > mechanism used to share metadata from other Simile > installations. If so then RDF becomes a transport format; > extraction and creation RDF from the data in the system is > through ingest and publish tools. > > > > On the semantic web, the client is programmatically > accessing SIMILE, > > or by web page, so issues of client-side caching, change > notification > > arise, as do security, and, potentially, charging and SLAs. > > This is the first I've heard of this. I thought Simile was a > standard web architecture application, using a web browser as > the client. 1/ Just using RDF as a transport format is not really utilizing RDF because the semantics are hidden in the internal processed representation and not necessarily preserved on converting into and out of RDF. As it is the internal semantics that matter (i.e. are first-class), you might as well use XML for a transport as you are relying on the converters to maintain the semantics across the Web. 2/ The PIs can say what SIMILE "is" but I don't see SIMILE as a standard web architecture application. That would make the functionality of the whole thing (database to client) one of defining the future uses and building it. Rather, I see it as a set of RDF stores, with a variety of services clustering around which transform RDF (not necessarily change: e.g. services that support query with answers in RDF), some services that use information from SIMILE and other sources in support of some community, and also some services that are concerned with presentation (e.g. RDF -> HTML in some loose sense). Web browsers are one way of displaying information but I don't see all these services being in the same logical place. My example of the schedules related to course material was supposed to bring out that some information comes from SIMILE while some comes from other sources, and it is combined by some service into a useful element. This dynamic information does not follow the formal ingestion process that, say, publication metadata does yet the community (here maybe students taking the course) would find the service useful in the way it combines SIMILE information with other sources. Where these services are located is not fixed and more an issue of deployment. They may be at SIMILE sites, on user machines or some third-part place. Places on the web that support various communities seem a likely model to me - a SIMILE site may have such services for the communities clustering around the information this SIMILE site contains. Andy PS we built a 3-tier Semantic Web Application here. It was OK but wasn't really very open - better for services to interact with each other rather than going to an underlying database. Single triple access to the DB was (predicably) not workable - sub entity bean granularity. We used queries - see http://www1.bcs.org.uk/DocsRepository/03700/3772/barnell.htm > > -- > ======================================================== > Kevin Smathers kevin.smathers@hp.com > Hewlett-Packard kevin@ank.com > Palo Alto Research Lab > 1501 Page Mill Rd. 650-857-4477 work > M/S 1135 650-852-8186 fax > Palo Alto, CA 94304 510-247-1031 home > ======================================================== > use "Standard::Disclaimer"; > carp("This message was printed on 100% recycled bits.");
Received on Monday, 7 April 2003 09:51:11 UTC