There are several improvements that KnEd needs before it is a complete system.
First, a better method for displaying inherited information is needed. One solution would be to add an operation to slots that would let the user toggle between displaying only the local values of the slot, or to display both the local and inherited values. But, this operation will only work for slots that appear locally on a frame. An additional mechanism is needed for displaying global information for slots that don't appear locally.
The tree panes currently only display trees from one root. Code written by Suzanne McBride [McBride:92] on the TI-Explorers greatly expanded the functionality of the tree panes. It let the user have multiple tree roots and the user could expand individual nodes in the tree. It also provides an interface to Liane Acker's viewpoints [Acker:92].
Another lost feature that needs to be reimplemented is the capability for the user to draw knowledge maps. Knowledge maps are drawings of relationships between frames. The user first places the frames on the screen and then draws relationships between them. After drawing the map, the user has the option of adding the information contained in the map to the knowledge base.
Figure 32: A user drawn knowledge map about Photosynthesis
The KnEd implementation on the TI-Explorers had this capability, but it was not ported to the workstation version of KnEd. Figure 32 is an example of a knowledge map drawn using the TI version of KnEd.
Figure 33: An example of a constraint menu
Currently, the users routinely ignore messages generated by the constraint checker. So, a new mechanism is needed that will capture these error messages and display them in a window. This window would give the user the option of ignoring the messages, changing the assertion (so that it might pass the constraint checker), or aborting the operation entirely (via delete). This menu may also be hidden if the user prefers to take care of the warning messages at a later time. In that case, the warning messages would collect in the window. Figure 33 is an example of a possible version of a constraint menu generated when an invalid value was added to the (Photosynthesis input-energy-form) address and the frame "Leaf" was misspelled.
One major problem faced by the text panes is the method in which they're updated. Currently, when a frame is updated, the display for the entire frame is recomputed. But, this is costly if the frame is large. What's needed is to only update the part of the display for which the frame has changed.
Lastly, another user-interface study needs to be done. Not only have new features have been added to KM since the Blumenthal study in 1990 [Blumenthal:90], but there are several issues that are still unresolved. For instance, the matrix in Table 2 needs to be evaluated to determine if the commands specified in the matrix are the ones used most frequently by the user. If not, then it might be better to move some of these commands to the frame, slot, value, and annotation menus and replace them with more frequently used commands.