Graphics Reference
In-Depth Information
application, enterprise, and community boundar-
ies. It is a collaborative effort led by W3C with
participation from a large number of researchers
and industrial partners. It is based on the Resource
Description Framework (RDF),” which is a stan-
dard model for defining information and the data
interchange on the web. Pieces of data and links
that connect them are identified as Universal
Resource Identifiers (called URIs). The common
Web addresses URLs are special forms of URIs.
In a semantic space, the meanings of words
may be represented numerically depending on
the frequency distributions of the words. The
semantic web analyzes the data on the web - the
content, links, and transactions between people
and computers, and provides common metadata
languages (such as Resource Description Frame-
work RDF) that describe information about web
resources to publish information. The Semantic
web came to being due to the development of the
XML standard. With the semantic web it is pos-
sible to share via the Internet large, formalized
collections of facts or data derived from study,
experience, or instruction. The grammar of the
XML derives from the semantics and involves
definitions of types for different objects, topics and
their occurrences, links between topics, relations
and interconnections between topics.
The content of the web can be conveyed not
only in languages written by people; it also can
be understood and used by software agents that
act for users or other programs. It means the
content of the web can be understood and used
not only by people but also by software, so the
semantic web analyzes the content, links, and
interactions between people and computers.
Soon web will provide an access to a semantic
web integrated across huge data resources. It is
a universal medium for data, information, and
knowledge exchange comprising text documents
(mostly in HTML language), images (mostly
graphics), audio and video files, animations, and
other materials such as data, applications, web
pages, e-services, or archived e-mail messages.
Thus, the semantic web comprises the philosophy,
design principles, collaborative working groups,
and technology, advancing the current web prog-
ress and allowing users to easily find, share, and
combine information. In a semantic space, the
meanings of words are represented numerically
depending on the frequency distributions of the
words; the relations are examined, in a network
of concepts using words and symbols as labels
for data. Information management of the data
and the web itself is transformed into semantic
web that bridges knowledge representation and
information management. The semantic web is a
web visualization tool that builds a virtual network
and makes possible sharing data and knowledge
by providing metaphors for web navigation and
communication through the Internet and hyper-
links. Semantic web builds relationships based on
a specific topic, for example on a scientific study,
while social networking attracts friends through
social connections.
Semantic web and personalized information
management employ ontologies - terms and data
that individuals or groups use and the relations
among those items. Ontologies represent the
semantic context of the domain and its classes
(Katifori, Torou, Halatsis, Lepouras, & Vassila-
kis, 2006). Ontology is a format description of a
domain that contains entities (classes). Thus, a
formal description of a domain can be done with
the ontology engineering environment tools for
semantic web services. Thus ontologies operate
above RDF and software programs called the
inference engines operate above ontologies (Fei-
genbaum et al., 2007). Several ontology visualiza-
tions are available through the existing ontology
management tools. Protégé and the Protégé-OWL
editor are tools that support the web ontology
language OWL that is endorsed by the World
Wide Web Consortium (W3C) - an organization
composed of hundreds of cooperating companies
and universities. Protégé uses several kinds of
visualization plug-ins for the representation of
the ontology. Plug-ins for web browsers can ren-
