What is a Name, an Address, an Author, a Document ?
What do they mean, to
you, to me, to the Inland Revenue, to Customs and Excise, to your customers, to
your suppliers ?
- Simple things first
- sitemaps, news channel syndication
- thesauri, classification, topic maps
- calandaring, scheduling, collaboration
- annotations, quality ratings, shared bookmarks
- dublin core for simple resource discovery
- web service description and discovery
- peer to peer (napster, gnutella etc.) & rights management
...and mixing all these together
- Getting more ambitious:
- extending RSS newsfeeds using XML namespaces
- Simple reasoning (ontologies, thesauri)
- digital signatures (trust, provenance)
- scalability issues
- user interface challenges
...and mixing all these together
Example 1 - Terminology/Thesauri/Ontology Definition - an RDF
application
The ELSST multi-lingual thesaurus of social science terms is encoded in RDF
to define the terms used in the vocabulary. Other organisations such as the UK
Government may also define these terms in their own ways.
Your applications can indicate which definition they are using.
The richer the definitions, then they move from being called term lists, to
thesauri to ontologies. W3C has a working group defining an ontology
representation language on top of RDF (DAML+OIL).
Example
RDF of ELSST thesaurus entry
Example 2 - Dublin Core Metadata - an RDF application
The Dublin Core defines in RDF a minimal set of characteristics about a
resource that would be needed by a resource discovery system. Descriptions can
be added to web pages, or to point to non-electronic resources such as library
books, museum objects etc.. Any resource can be described in the Dublin Core.
- Title
Label: Title
The name given to the
resource, usually by the Creator or Publisher..
- Author or Creator
Label: Creator
The
person or organization primarily responsible for creating the intellectual
content of the resource. For example, authors in the case of written
documents, artists, photographers, or illustrators in the case of visual
resources.
- Subject and Keywords
Label: Subject
The
topic of the resource. Typically, subject will be expressed as keywords or
phrases that describe the subject or content of the resource. The use of
controlled vocabularies and formal classification schemas is encouraged.
- Description
Label: Description
A
textual description of the content of the resource, including abstracts in the
case of document-like objects or content descriptions in the case of visual
resources.
- Publisher
Label: Publisher
The entity
responsible for making the resource available in its present form, such as a
publishing house, a university department, or a corporate entity.
- Other Contributor
Label:
Contributor
A person or organization not specified in a Creator element who
has made significant intellectual contributions to the resource but whose
contribution is secondary to any person or organization specified in a Creator
element (for example, editor, transcriber, and illustrator).
- Date
Label: Date
A date associated with the
creation or availability of the resource. Recommended best practice is defined
in a profile of ISO 8601 ( http://www.w3.org/TR/NOTE-datetime
) that includes (among others) dates of the forms YYYY and YYYY-MM-DD. In
this scheme, the date 1994-11-05 corresponds to November 5, 1994.
- Resource Type
Label: Type
The category of the resource, such
as home page, novel, poem, working paper, technical report, essay, dictionary.
For the sake of interoperability, Type should be selected from an enumerated
list that is under development in the workshop series.
- Format
Label: Format
The data format and,
optionally, dimensions (e.g., size, duration) of the resource. The format is
used to identify the software and possibly hardware that might be needed to
display or operate the resource. For the sake of interoperability, the format
should be selected from an enumerated list that is currently under development
in the workshop series.
- Resource Identifier
Label:
Identifier
A string or number used to uniquely identify the resource.
Examples for networked resources include URLs and URNs (when implemented).
Other globally-unique identifiers, such as International Standard Book Numbers
(ISBN) or other formal names would also be candidates for this element.
- Source
Label: Source
Information about a
second resource from which the present resource is derived. While it is
generally recommended that elements contain information about the present
resource only, this element may contain metadata for the second resource when
it is considered important for discovery of the present resource.
- Language
Label: Language
The language of
the intellectual content of the resource. Recommended best practice is defined
in RFC 1766 http://info.internet.isi.edu/in-notes/rfc/files/rfc1766.txt
- Relation
Label: Relation
An identifier
of a second resource and its relationship to the present resource. This
element is used to express linkages among related resources. For the sake of
interoperability, relationships should be selected from an enumerated list
that is currently under development in the workshop series.
- Coverage
Label: Coverage
The spatial
and/or temporal characteristics of the intellectual content of the resource.
Spatial coverage refers to a physical region (e.g., celestial sector) using
place names or coordinates (e.g., longitude and latitude). Temporal coverage
refers to what the resource is about rather than when it was created or made
available (the latter belonging in the Date element). Temporal coverage is
typically specified using named time periods (e.g., Neolithic) or the same
date/time format ( http://www.w3.org/TR/NOTE-datetime
) as recommended for the Date element.
- Rights Management
Label: Rights
A rights
management statement, an identifier that links to a rights management
statement, or an identifier that links to a service providing information
about rights management for the resource.
Example
RDF header for Dublin Core Metadata
