Adaptive Hypermedia Applications
In an adaptive hypermedia application the content and the
link structure of the application are adapted to the individual user.
A lot of research has been done on adaptive hypermedia applications.
We only show some aspects that are relevant for the use of the
AHA system.
Content Adaptation
The content of pages can be changed in two ways:
- For various reasons fragments or multimedia objects
can be conditionally included in an otherwise fixed presentation.
In some systems only certain conditional inclusions are possible
(e.g. through "stretchtext" or "page variants").
AHA offers the most versatile but also the lowest-level conditional
inclusion mechanism.
- Information items may also be conditionally rearranged or
sorted. Some systems may even dynamically generate the entire
content of pages. AHA offers no such features.
Link Adaptation
Many ways of adapting the links exist, including adaptive
graphical overviews, adaptive global guidance buttons, etc.
Techniques relevant for AHA are:
- Link hiding is a technique where (temporarily) undesirable
links are hidden by displaying them as regular text. This is the default
link adaptation in the AHA system. In order for this technique to work
links must not be underlined.
- Link annotation is a technique where desirable and undesirable
links are shown in different colors. Several adaptive hypermedia systems
offer this technique. In AHA the colors for desirable and undesirable
links can be reconfigured by the end-user. By doing this the end-user
can change AHA's behavior from link hiding to link annotation.
- Link removal is a technique where the link anchors for
undesirable links are removed. To do this in AHA requires the use of
content adaptation. (In fact, the link anchor is a content fragment
that can be conditionally removed.)
- Link disabling is a technique where the link remains
visible, but cannot be followed. To do this in AHA also requires the use
of content adaptation. The link anchor can be replaced by the same text,
shown in the link color but without it being a link anchor.
As you browse through this tutorial you will experience the use of
these content and link adaptation techniques being used.