The
BBC
The British Broadcasting Corporation (BBC) is a British public service broadcaster headquartered at Broadcasting House in London, England. Originally established in 1922 as the British Broadcasting Company, it evolved into its current sta ...
's Lonclass ("London Classification") is a subject classification system used internally at the BBC throughout its
archives
An archive is an accumulation of historical records or materials, in any medium, or the physical facility in which they are located.
Archives contain primary source documents that have accumulated over the course of an individual or organ ...
.
Lonclass is derived from the
Universal Decimal Classification
The Universal Decimal Classification (UDC) is a bibliographic and library classification representing the systematic arrangement of all branches of human knowledge organized as a coherent system in which knowledge fields are related and inter-lin ...
(UDC), itself a reworking of the earlier
Dewey Decimal Classification
The Dewey Decimal Classification (DDC) (pronounced ) colloquially known as the Dewey Decimal System, is a proprietary library classification system which allows new books to be added to a library in their appropriate location based on subject. ...
(DDC). Lonclass dates from the 1960s,
whereas UDC was created from DDC in the late 19th century. The BBC adaptation of UDC preserves the core features that distinguish UDC from DDC: an emphasis on a compositional semantics that allows new items to be expressed in terms of relationships between known items.
Lonclass and UDC (like DDC) are expressed using codes based on decimal numbers. Unlike DDC, the Lonclass and UDC codes use additional punctuation to express patterns of relationships and re-usable qualifiers. While Lonclass makes a few structural adjustments to the UDC system to support its emphasis on TV and radio content, its main distinction is in the actual set of topics that are recorded within its authority file and within specific BBC catalogue records. Unlike UDC and DDC, which are widely used across the library community, Lonclass has remained a BBC-internal system since its creation in the 1960s.
There are 300,000 subject terms in the Lonclass vocabulary.
[Dowman, M.; V. Tablan, H. Cunningham, C. Ursu, and
B. Popov. (2005). "Semantically Enhanced Television News through Web and Video Integration." In ''Second European Semantic Web Conference (ESWC’2005)''.]
Examples
For example, a Lonclass or UDC code may represent "Report on the environmental impact of the decline of
tin mining
Tin mining began early in the Bronze Age, as bronze is a copper-tin alloy. Tin is a relatively rare element in the Earth's crust, with approximately 2 ppm (parts per million), compared to iron with 50,000 ppm.
History
Tin extraction and use ca ...
in Sweden in the 20th century". This would be represented as a sequence of numbers and punctuation. The complex code can be broken down into primitives such as "Sweden" or "tin mining" (which itself could be broken down to "Tin" and "Mining").
Some specific BBC Lonclass examples (with explanatory labels):
* R672:32.007(47)YELTSIN:342.518.1THATCHER "TWO SHOTS OF MARGARET THATCHER AND BORIS YELTSIN"
*
RITISH AEROSPACE007.11PEARCE: 656.881:342.518.1THATCHER "LETTER TO MRS THATCHER FROM SIR AUSTIN PEARCE"
* 656.881:301.162.721:32.007THATCHER: 654.192.731TV-AM "MARGARET THATCHER'S LETTER OF APOLOGY TO TV AM"
* 656.881:301.162.721 "LETTERS OF APOLOGY"
* 656.881 "LETTERS (POSTAL SERVICES)"
* 656.881:06.022.6 "RESIGNATION LETTERS"
* 654.192.731TV-AM "TV AM (TELEVISION AM)"
Notes
{{reflist
External links
Using web-scale vocabularies to create user journeys across the BBC by Silver Oliver, Georgi Kobilarov, Chris Sizemore (Dublin Core conference presentation)
Investigating Lonclass (NoTube project slides)Lonclass and RDF discussion of relationship to
RDF
Semantically Enhanced Television News through Web and Video Integration(ACEMedia project report mentioning Lonclass)
Building bridges: mapping diverse taxonomies for a seamless user navigation experience(Fran Alexander, Taxonomy Manager, BBC Information and Archives, December 2010)
experimental ruby/treetop parser
Lonclass
1960s establishments in the United Kingdom
Classification systems
Library cataloging and classification