Topic Maps
— Overview and Basic Concepts
ISO (the International Organization for Standardization) and
IEC (the International Electrotechnical Commission) form the
specialized system for worldwide standardization. National bodies
that are members of ISO or IEC participate in the development of
International Standards through technical committees established by
the respective organization to deal with particular fields of
technical activity. ISO and IEC technical committees collaborate in
fields of mutual interest. Other international organizations,
governmental and non-governmental, in liaison with ISO and IEC, also
take part in the work. In the field of information technology, ISO and
IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the
rules given in the ISO/IEC Directives, Part 2.
ISO/IEC 13250-1
was prepared by Joint Technical Committee
ISO/IEC JTC 1, Information Technology, Subcommittee SC 34, Document
Description and Processing Languages.
ISO/IEC 13250
consists of the following parts, under the
general title Topic Maps:
- Part 1:
Overview and Basic Concepts
- Part 2:
Data Model
- Part 3:
XML Syntax
- Part 4:
Canonicalization
- Part 5:
Reference Model
- Part 6:
Compact Syntax
- Part 7:
Graphical Notation
Topic maps are collections of information about subjects and
relationships between subjects. Topic maps can be used:
-
To create navigational tools such as indexes,
cross-references, citation systems, or glossaries for information systems
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To create thesaurus-like interfaces to corpora, knowledge
bases, etc.
-
To create views of information systems that are filtered on
the basis of language, security criteria, or any other useful basis
-
To give unstructured information resources the appearance
of structure for navigation or for use with other structured
information resources
-
To provide contexts for subjects and relationships between
subjects. (Context can be used to address the polysemy problem
faced by WWW search engines.)
Two models are included in this standard. Those are Part-2: Data model (TMDM) and Part-5: Reference model (TMRM).
TMDM specifies a data model of Topic Maps. It defines the abstract
structure of Topic Maps, using the information set formalism. TMDM
provides a foundation for the syntaxes and notations defined in other
parts of this standard (except TMRM), and the query and constraint
languages defined in accompanying standards.
TMRM is called subject maps. TMRM provides higher level models for
Topic Maps and specifies the following:
-
a formal model for subject maps
-
minimal access functionality and for information retrieval from subject maps
-
a constraint framework governing the interpretation of subject maps
-
a path language for ISO/IEC 18048 Topic Maps Query Language (TMQL) and ISO/IEC 19756 Topic Maps Constraint Language (TMCL)
The mapping the constructs of the TMDM to TMRM is described in TMRM.
Topic Maps
— Overview and Basic Concepts
ISO/IEC 13250 Topic Maps consists of the following parts:
-
ISO/IEC 13250-1: Topic Maps -- Overview and Basic Concepts
-
ISO/IEC 13250-2: Topic Maps -- Data Model
-
ISO/IEC 13250-3: Topic Maps -- XML Syntax
-
ISO/IEC 13250-4: Topic Maps -- Canonicalization
-
ISO/IEC 13250-5: Topic Maps -- Reference Model
-
ISO/IEC 13250-6: Topic Maps -- Compact Syntax
-
ISO/IEC 13250-7: Topic Maps -- Graphical Notation
This International Standard does not require any particular model
for processing of topic maps.
Except as required or disallowed by any particular part of this
Standard, any scheme may be used for addressing information objects.
The following referenced documents are indispensable for the
application of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the
referenced document (including any amendments) applies.
ISO/IEC 13250-2, Topic Maps — Data Model
ISO/IEC 13250-3, Topic Maps — XML Syntax
ISO/IEC 13250-4, Topic Maps — Canonicalization
ISO/IEC 13250-5, Topic Maps — Reference Model
ISO/IEC 13250-6, Topic Maps — Compact Syntax
ISO/IEC 13250-7, Topic Maps — Graphical Notation
ISO/IEC 18048, Topic Maps — Query Language
ISO/IEC 19756, Topic Maps — Constraint Language
ISO/IEC 29111, Expressing Dublin Core Metadata using Topic Maps
ISO/IEC 13250-1 provides an overview of each part of ISO 13250 and
how the parts fit together into a coherent whole.
ISO/IEC 13250-2 specifies a data model for topic maps. It defines
the abstract structure of topic maps, using the W3C infoset formalism,
and to some extent their interpretation, using prose. The default
rules for merging in topic maps are also defined, as are some
fundamental published subjects.
13250-2 underlies 13250-3, -4, -6, -7 and is used by ISO/IEC 18048 Topic
Maps Query Language (TMQL) and ISO/IEC 19756 Topic Maps Constraint
Language (TMCL).
ISO/IEC 13250-3 defines the XML Topic Maps 2.0 (XTM) interchange
syntax for topic maps, a syntax based on XML, XPointer, and IRIs. The
allowed syntactical expressions in XTM documents are constrained using
a RELAX-NG schema for XTM 2.0 and prose, and their interpretation is defined using
13250-2. The semantics of this syntax is defined by 13250-2.
ISO/IEC 13250-4 defines transformation of an an instance of the
Topic Maps Data Model (ISO/IEC 13250-2) into an instance of the XML
Infoset model. It further defines the sort order of any set of
informaton items from that model.
ISO/IEC 13250-5 defines an abstract model of topic maps that
supports the definition of path languages for higher level models for
topic maps. The requirements for such models is also defined. 13250-5
underlies ISO/IEC 18048 Topic Maps Query Language (TMQL) and ISO/IEC
19756 Topic Maps Constraint Language (TMCL).
ISO/IEC 13250-6 defines a compact syntax as an alternative to the
more verbost XML syntax defined in ISO/IEC 13250-3. The two syntaxes
are identical in terms of their import and processsing according to
ISO/IEC 13250-2 (Topic Maps Data Model) and ISO/IEC 13250-4 (Topic
Maps Canonicalization).
ISO/IEC 13250-7 defines a graphical notation for the representation
of topic maps for use in designing, explaining, teaching or other
circumstances where a non-syntax representation of a topic map is
deemed useful.
The relationship of each part and how they fit together is shown in
figure 1.
Figure 1 —
Relationship of Topic Maps Standards
-
TMDM: defines topic map constructs and rules for those constructs
-
TMDM provides the foundation for the syntaxes and notations defined in Parts 3 XML Syntax (XTM), Part 4 Canonicalization (CXTM),
Part 6 Compact Syntax (CTM), and Part 7 Graphical Notation (GTM), and ISO/IEC 18048 Query Language (TMQL) and ISO/IEC 19756
Constraint Language defined in accompanying standards.
-
TMRM: has three parts: formal model; path language; constraints
on models
-
TMDM: uses the TMRM as a formal model and constraints on model
(but not the path language)
-
TMCL follows the TMDM for topic map constructs and their rules
but is not limited to those rules and uses the TMRM for a path
language
-
TMQL depends on TMDM for topic maps constructs and their rules
but is not limited to those rules and uses the TMRM for a
path language
The benefits and promising applications of Topic Maps include:
-
Semantic Indexing
The volume of accessible information is
exploding at an exponential rate. Search engine results are symptons
of and not solutions to that problem. Topic maps offer:
-
Subject-based organization (everything organized around topics)
-
Associative model (very intuitive navigation)
-
Structured queries (adds more power to full-text search)
Examples of the semantic indexing applications are as follows:
-
Taxonomy management
-
Metadata management
-
Semantic portals
- Knowledge Management
Every organization faces the challenge of
the managing knowledge of its staff. Capturing and sharing knowledge
that knowledge is a key factor of organization's success. Topic Maps
provides ideal solution for this problem for the following reasons:
-
It captures knowledge as expressed by people
-
The resulting topic maps can be merged
-
They are based on an International Standard.
Examples of the Knowledge Management are as follows:
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Business process management
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Product configuration
-
Business rules management
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IT asset management
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Manufacturing asset management
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Intelligence gathering and analysis
-
e-Learning
Knowledge is at the core of e-Learning. Computers support the
acquisition of knowledge by humans. Topic Maps provides an excellent
model to capture knowledge acquisition by:
-
Capturing what the pupil has learned
-
Structuring eLearning systems
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Organizing school and university curricula
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And enabling the merging of topic maps built for such resources.
ISO/IEC 13250:2003, Topic Maps, 2003, http://www.y12.doe.gov/sgml/sc34/document/0322_files/iso13250-2nd-ed-v2.pdf
XTM1.0, XML Topic Maps (XTM) 1.0 Specification, Steve Pepper, Graham Moore, TopicMaps.Org, 2001, http://www.topicmaps.org/xtm/1.0/
