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RE: [ba-ohs-talk] Fenfire, RDF (re "Towards a Standard Graph-Based...")

Hi Benja,    (01)

> Toni Alatalo pointed me to your paper, `Towards a Standard Graph-Based
> Data Model for the Open Hyperdocument System`__. You make the point that
> a standard graph-based model could allow different applications to be
> integrated into a single whole. You say that RDF is one possible choice
> for a modeling language, but reject it because of its complicated syntax.
> __ http://www.eekim.com/ohs/papers/graphmodel/    (02)

I couldn't find the 'rejection' bit on a skim of Eugene's paper...but
whatever, I'm getting the impression that an implementation of an OHS is
actually well on its way, primarily using the RDF model. Pretty much daily
I'm coming across new RDF-based systems that focus on different aspects of
the general problem (many blogged at [1]), and these may considered as a
whole thanks to the shared language - there are obviously other models in
use for this kind of thing (notably TM) but I think RDF is likely to emerge
as the common language, largely thanks to its lowest-common-denominator
statement representation. In other words, the development itself is
distributed - which seems quite natural really.    (03)

I can't remember seeing anyone taking the zigzag idea specifically and
putting it in RDF, so it'll be interesting what happens with Gzz/Fenfire
along these lines. I note that Fenfire is described as a hyperstructured
UI - this will be good to see, as UI development is lagging behind in RDF
developments.    (04)

> Our aim is very close to what you describe; we want information from any
> application on a computer system (or network) to be available for
> linking with information from any other application, in any linking
> structure (for example IBIS discussion). For a person I'm in contact
> with, there should be a single node on my computer, connected to their
> address, their birthday, my appointments with them, emails I received
> from them, photos of them, and so on.    (05)

That would be a foaf:Person [2] I take it?    (06)

> So, I'm hoping for some discussion about whether RDF is the right choice
> for these goals. Your concern about RDF is the RDF/XML serialization
> syntax. However, the RDF model is specified independently (`Concepts and
> Abstract Syntax`_) from its serialization (`RDF/XML Syntax
> Specification`_).    (07)

Quite. An awful lot of the naysaying about RDF on xml-dev and elsewhere has
been a direct result of the ugly serialization - the model is relatively
simple & (reasonably!) elegant, yet powerful enough to do what's required -
I for one think it's the best choice of the current field.    (08)

For Fenfire, we need a canonical format for RDF graphs, so that
> equal RDF graphs are always serialized to the same byte sequence; we
> might invent our own serialization language for that.    (09)

Why do you need the same byte sequence?
Anyhow it should be pretty straightforward to achieve - e.g. alphabetically
sorted nTriples.    (010)

>  From my cursory look, it seems that GXL uses URIs for edges (thus
> providing orthogonality) but not for nodes (thus not providing
> location-independent links). GSIX seems to use local identifiers for
> both edges and nodes.    (011)

As well as a way of defining nodes and arcs, a means of unambiguously
binding semantics to them is required, and I reckon that if you applied this
step to something like GXL you would end up with something along the same
lines as RDF. (I'm not familiar with GSIX)    (012)

...all structures should be viewable in a
> single 'structure editor' (even though we'll have all sorts of different
> views for application-specific data which you can switch forth and back
> between-- we share the OHS's vision here).    (013)

Ideagraph [3] is my own take on this, and I agree absolutely with your
reasoning behind the use of RDF (though am too lazy to express it myself ;-)    (014)

Danny.    (015)

[1] Semantic Web blog
http://www.citnames.com/blog    (016)

[2] 'Friend of a friend' vocabulary
http://xmlns.com/foaf/0.1/    (017)

[3] http://ideagraph.net    (018)