3.3. Node landmark model
The node landmark model is a model that defines relations
between nodes and landmarks. An example of this
model is shown in Fig. 5. Some landmarks, such as large
buildings, are used as landmarks from multiple navigation
points. In conventional navigation systems, a landmark has
only one guide annotation, such as a photo and a name,
even when the physical appearance of the landmark changes
according to the point from which it is observed. However, if
a landmark has only one picture as a guide annotation, users
may not recognize the landmark from the picture because
the picture may have been taken from a different observation
point. Thus, the model does not only add guide annotations
to landmarks but also defines the relation between intersections
and landmarks and adds those pieces of information
to it. This method makes it possible to add a variety of
information to landmarks according to the position from
which it is viewed. As a result, it is possible to provide
appropriate navigation that corresponds to user location.