ali alshowaish. collective realization that machine-processability requires a coherent data model a...

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Ali Alshowaish

Collective realization that machine-processability requires a coherent data model

A casual discussion at WWW-2 in Chicago, October of 1994 How to make things on the Web easier to find?

OCLC & NCSA co-sponsored an invitational workshop in March of 1995

The workshop became a workshop series, and eventually a conference series

DCMI: Dublin Core Metadata Initiative Governance and process evolved over time Unofficial standards maintenance body

established

1994: Simple tags to describe Web pages 1995: The Dublin Core is one of many

vocabularies needed ("Warwick Framework")

1996: The Dublin Core: 13 elements expanded to 15 - appropriate for Text and Images

1997: “Qualifiers” proposed for specifying meanings

1998: DCMI involvement in emerging Resource Description Framework (RDF)

2000: Dublin Core Metadata Initiative recommends (approved) qualifiers, broadens its organizational scope beyond the Core

2001: Workshop Series becomes a conference series

DCMI Affiliates and a board of trustees 2005: Abstract Model (Finally)

A simple standard set of metadata elements used primarily to describe digital resources such as video, sound, image, text, and web pages.

It defines resources online in a way that make them easy to find.

Implementations of Dublin Core typically make use of XML and are Resource Description Framework based.

Dublin Core is defined by ISO in ISO Standard 15836, and NISO Standard Z39.85-2007

The continuing development of Dublin Core is managed by the Dublin Core Metadata Initiative (DCMI).

Creator Title Subject

Contributor Date Description

Publisher Type Format

Coverage Rights Relation

Source Language Identifier

In HTML there is only one meta tag? And all the Metadata elements have to be inside that tag.

• 2 parts for each element (html format) meta name=" " content=" "

• Because of that all the Dublin Core elements in HTML are attributes.

<meta name="dc.title" content="Sustaining the Environment and Resources for Canadians - What is it?" ><meta name="dc.creator" content="Government of Canada, Environment Canada, Deputy Minister's Office" >

<meta name="dc.title" content="Sustaining the Environment and Resources for Canadians - What is it?" ><meta name="dc.creator" content="Government of Canada, Environment Canada, Deputy Minister's Office" >

<meta name="dc.title" content="Allergy Alert - Undeclared Sulphites in Al-Durra/Alderra Brand Whole Apricots in Syrup Product "><meta name="dc.creator" content="Government of Canada, Canadian Food Inspection Agency, Operations, Office of Food Safety and Recall"><meta name="dc.subject" content=”Food safety; Labelling; Food labelling; Consumers; Consumer protection"><meta name="dc.date" content="2002-01-31"><meta name="dc.language" content="eng"><meta name="dc.description" content="The Canadian Food Inspection Agency (CFIA) is warning consumers with sensitivities to sulphites not to consume AL-Durra/Alderra brand whole apricots in syrup product. This product may contain sulphites which are not declared on the label."><meta name="dc.publisher" content= Government of Canada, Canadian Food Inspection Agency“>

In XML each Metadata element has its own tag.

• In XML the Dublin Core element are not attributes, but separate elements.

<dc:title>Jefferson Monument, Louisville, Ky. </dc:title><dc:description>The Thomas Jefferson monument in Louisville, Kentucky. Jefferson stands upon a pedestal supported by four winged female figures; he holds a partially unrolled scroll. The pedestal, Jefferson's figure and the sky behind the statue are colorized; the base is grey. This monument was given to the city of Louisville by Isaac W. Bernheim. The verso bears a postmark of May 5, 1913.</dc:description><dc:subject>Monuments &amp; memorials; Jefferson, Thomas, 1743-1826--Monuments;</dc:subject><dc:coverage>Louisville (Ky.)</dc:coverage><dc:date>1913-03-23</dc:date><dc:type>Still image</dc:type><dc:publisher>Early American Museum</dc:publisher><dc:language>eng</dc:language><dc:identifier>http://digital.library.universityedu/u?/ulua001,98</dc:identifier>

RDF: Resource Description Framework. Input from various communities (several

Metadata schemas) Enables resource description communities to

define their own semantics

<?xml version="1.0"?><rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-

ns#" xmlns:dc="http://purl.org/dc/elements/1.0/">

<rdf:Description rdf:about="http://www.ukoln.ac.uk/metadata/resources/dc/datamodel/WD-dc-rdf/">

<dc:title> Guidance on expressing the Dublin Core within the Resource Description Framework (RDF) </dc:title>

<dc:creator> Eric Miller </dc:creator><dc:creator> Paul Miller </dc:creator><dc:creator> Dan Brickley </dc:creator><dc:subject> Dublin Core; Resource Description Framework;

RDF; eXtensible Markup Language; XML </dc:subject><dc:publisher> Dublin Core Metadata Initiative </dc:publisher><dc:contributor> Dublin Core Data Model Working Group

</dc:contributor><dc:date> 1999-07-01 </dc:date><dc:format> text/html </dc:format><dc:language> en </dc:language></rdf:Description></rdf:RDF>

It consist of 15 elements. All elements optional All elements repeatable where

appropriate . It may appear in any order the creator of

the metadata wishes. Extensible (DC Qualifiers) International in scope, however, DC

syntax is not translated

The namespace syntax in HTML is like this: dc.title

The namespace syntax in XML is like this: dc:title

Use lower case for DC tags dc:title Not: DC:TITLE or Dc:title or Dc:Title

dc.creator indicates who is primarily responsible for creating the content of the resource.

dc.creator example:<meta name="dc.creator" content=“Hamad Aljasser">

<meta name="dc.creator" content="Government of Canada, Department of Canadian Heritage, Parks Canada Agency">

dc.creator element should reflect organizational hierarchy .

Avoid abbreviations and acronyms Repeat the creator element to acknowledge

important participants.

dc.title indicates name given to the resource.

dc.title example: <meta name="dc.title" content=“American

Rural Information Service "> If the resource described is a website, Ideally,

the content for <dc.title> should be identical to the HTML <title> </title>

dc:language indicates the language of the intellectual content of the resource.

dc.language examples: <meta name="dc.language“ content="eng">

<meta name="dc.language” content="fre">

Since the field is repeatable, it may describe documents in many languages.

Language names should be described in some standard encoding scheme such as ISO639.

dc.date indicates a date associated with a resource.

dc.date examples:<meta name="dc.date" content="2002-04-16">

<meta name=”dc.date” content=”2003-02-20”>

Format is YYYY-MM-DD (e.g. 2003-03-15) Fill in unknown year with “?”

(e.g. 199?-01-01) Fill in unknown month and day with 01

(e.g. 1995-01-01)

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