- From: Graham Klyne <gk@ninebynine.org>
- Date: Fri, 09 May 2003 19:57:44 +0100
- To: Brian McBride <bwm@hplb.hpl.hp.com>, w3c-rdfcore-wg@w3.org
Brian, I don't know... I thought I was just following up an assigned action, and didn't go checking for wider context: [[ williams-01 (revised proposal): http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Apr/0199.html latest amendment reflect comment from Patrick http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Apr/0192.html RESOLVED: williams-01 is rejected, but the text is made more consistent as in msg 0199 UNANIMOUS ACTION jjc update CONCEPTS in light of decision williams 01 ACTION gk respond wrt williams 01 ]] -- http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Apr/0207.html (agendum 16) #g -- At 11:54 09/05/2003 +0100, Brian McBride wrote: >At 14:10 11/04/2003 +0100, Graham Klyne wrote: > >>With reference to: >> http://www.w3.org/2001/sw/RDFCore/20030123-issues/#williams-01 > >Which is closed an accepted: > http://www.w3.org/2001/sw/RDFCore/20030123-issues/#williams-01 > >did I mess up somewhere? > >Brian > > > >>I propose that this comment is addressed by revised text at: >>http://www.ninebynine.org/wip/RDF-concepts/20030401/Overview.html#section-data-model >>http://www.ninebynine.org/wip/RDF-concepts/20030401/Overview.html#section-URI-Vocabulary >>(copied below) >> >>This revision is to bring the introduction of the RDF graph concept, and >>its use of URIs, into line with the agreed model [1], as articulated by >>Pat [2]. The text has been revised from my original proposal in response >>to discussion on the RDFcore list. The change in terminology (property >>-> predicate) means that the GIF image used section 3.1 is revised. >> >>[1] [[[ref?]]] >>[2] http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Feb/0152.html >> >>I also note that the description of abstract graph syntax in section 6 is >>already consistent with this model. >> >>#g >>-- >> >> >>[[ >>3.1 Graph data model >> >>The underlying structure of any expression in RDF is a collection of >>triples, each consisting of a subject, a predicate and an object. A set >>of such triples is called an RDF graph (defined more formally in section >>6). This can be illustrated by a node and directed-arc diagram, in which >>each triple is represented as a node-arc-node link (hence the term "graph"). >> >> [image of the RDF triple comprising (subject, predicate, object)] >> >>Each triple represents a statement of a relationship between the things >>denoted by the nodes that it links. Each triple has three parts: >> >> 1. a subject, >> 2. an object, and >> 3. a predicate (also called a property) that denotes a relationship. >> >>The direction of the arc is significant: it always points toward the object. >> >>The nodes of an RDF graph are its subjects and objects. >> >>The assertion of an RDF triple says that some relationship, indicated by >>the predicate, holds between the things denoted by subject and object of >>the triple. The assertion of an RDF graph amounts to asserting all the >>triples in it, so the meaning of an RDF graph is the conjunction (logical >>AND) of the statements corresponding to all the triples it contains. A >>formal account of the meaning of RDF graphs is given in [RDF-SEMANTICS]. >> >> >>3.2 URI-based vocabulary >> >>A node may be a URI with optional fragment identifier (URI reference, or >>URIref), a literal, or blank (having no separate form of >>identification). Properties are URI references. (See [URI], section 4, >>for a description of URI reference forms, noting that relative URIs are >>not used in an RDF graph. See also section 6.4.) >> >>A URI reference or literal used as a node identifies what that node >>represents. A URI reference used as a predicate identifies the >>relationship between the nodes it connects. A predicate URI reference >>may also be a node in the graph. >> >>A blank node is a node that is not a URI reference or a literal. In the >>RDF abstract syntax, a blank node is just a unique node that can be used >>in one or more RDF statements, and has no globally distinguishing identity. >> >>A convention used by some linear representations of an RDF graph to allow >>several statements to reference the same unidentified resource is to use >>a blank node identifier, which is a local identifier that can be >>distinguished from all URIs and literals. When graphs are merged, their >>blank nodes must be kept distinct if meaning is to be preserved; this may >>call for re-allocation of blank node identifiers. Note that such blank >>node identifiers are not part of the RDF abstract syntax, and the >>representation of triples containing blank nodes is entirely dependent on >>the particular concrete syntax used. >>]] >> >> >>------------------- >>Graham Klyne >><GK@NineByNine.org> >>PGP: 0FAA 69FF C083 000B A2E9 A131 01B9 1C7A DBCA CB5E > >------------------- >Graham Klyne ><GK@NineByNine.org> >PGP: 0FAA 69FF C083 000B A2E9 A131 01B9 1C7A DBCA CB5E
Received on Friday, 9 May 2003 15:10:55 UTC