- From: Jonathan Borden <jonathan@openhealth.org>
- Date: Fri, 20 Sep 2002 08:57:35 -0400
- To: "David Orchard" <dorchard@bea.com>, "'Tim Bray'" <tbray@textuality.com>, "'Norman Walsh'" <Norman.Walsh@Sun.COM>
- Cc: <www-tag@w3.org>
I want to expand on the following explanation: > > A URIref is a _label_ for a _node_. Each URIref uniquely and unambiguously > labels the node. Not all nodes are required to have labels. Nodes may have > properties and these properties may relate one node to another. > > Now suppose that these nodes just somehow exist, represented in some > database somewhere and let's suppose that these nodes might have labels and > that the labels consist of a string of characters having a given syntax.. > > One day, someone brings in a new box and attaches it to the node database. > This box accepts tickets that contain, among other things, the label for a > particular node. When you insert the ticket into the box, out pops a > printout describing the labelled node. The ticket allows you to specify > whether you want the description in English, Spanish, French and a few other > languages (this is an example of one of the other things that one might put > on a ticket). > The explanation is really simple because we haven't said how we are going to build the box, so I wanted to add a few thoughts to my previous message, but these thoughts don't affect the explanation I've given. There are roughly two ways to build the box that accepts a label and returns a description: In the first, a description of a node is simply written down and stored in some database (not the node database itself, but another database). When the ticket is presented, the label is used to retrieve the description from the database and print it out. When different languages are presented, the label and language is used to retrieve the description. Perhaps some descriptions might be pictures etc. (consider a picture as a variant of a language). In the second, the node database is accessed, and a program constructs a description from the known properties of the labelled node. The first mechanism corresponds to classic document storage and retrieval systems, the second to classic KR systems. Most actual systems will use elem ents of both techniques. Jonathan
Received on Friday, 20 September 2002 09:15:16 UTC