Information Technology Reference
In-Depth Information
flexible structured virtual museum or virtual shopping mall based on knowledge
in the information base. In this section, we explain these concepts and their
component based implementation framework.
2.1 The Notion of Context
A context consists of an identifier
c
plus
acontent
. The content of c is a set of
triplets of the form
< names,objectidentifier,reference >
where
names
is a set of descriptions for the object and
reference
is a context
identifier or Nil. The context referenced by an object contains information rel-
evant to that object. It is important to note that
names
and
references
are
context dependent. An object can belong to different contexts and may have
different names and/or different references in each context. This feature is useful
when we want to view an object from different perspectives
Accessing information in a contextualized information base often involves nav-
igating from one object to another by following references. From an object within
a given context, we can reach any object that belongs to its reference and, re-
cursively, any object that lies on a path. Navigation is based on the notion of
path.
2.2 Overview of CIAS
In order to create a CIAS, we map the components of a context into individual
virtual spaces. A context identifier is mapped into an individual virtual space,
called a
context space
. Each triplet in the content of the context is mapped into
an individual virtual space, called an
object space
. Therefore, an object space is
a 3D visualization of a triplet, a context space includes a set of object spaces,
and a CIAS is a set of context spaces.
A CIAS supports context traversal as multiple virtual space traversals: ac-
cessing a context, and accessing an object within the context. When a user is
inside a context space, the user will see a set of Object Space Ports (OSPs),
which is pointers to object spaces. The user may focus on one of the OSPs in
the context. Then the user is navigated to an object space by choosing one of
the OSPs. If a user is interested in the current object, then the user can go to a
relevant context space through a Context Space Port (CSP) in a current object
space. In its context space, there are OSPs of relevant information again. Users
can choose the context space, enter it, and follow the links depending on their
interests.
2.3 The Mechanism for Creating a CIAS
In this section, we focus on the development of generating Information Access
Space from existing Contextualized Information Bases. It is impossible to ma-
terialize all spaces and objects corresponding to all data in a large information
