Overview
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The GKB-Editor (Generic Knowledge Base Editor) is a tool for graphically
browsing and editing knowledge bases across multiple Frame Representation
Systems (FRSs) in a uniform manner. It offers an intuitive user interface,
in which objects and data items are represented as nodes in a graph, with
the relationships between them forming the edges. Users edit a KB through
direct pictorial manipulation, using a mouse or pen. A sophisticated
incremental browsing facility allows the user to selectively display only
that region of a KB that is currently of interest, even as that region
changes.
The GKB-Editor consists of three main modules: a graphical interactive display, based upon Grasper-CL, a library of generic knowledge-base functions, and corresponding libraries of frame-representation specific methods, both based upon the Generic Frame Protocol (GFP). When the user manipulates the display (e.g., editing the entry corresponding to the type of radar on an SA-4), generic functions are called (e.g., the put-slot-value function is called with the SA-4 frame, the radar-type slot, and the value pathand), which invoke the corresponding frame representation specific methods (e.g., the put-slot-value method for the Loom knowledge representation system from USC/ISI), which result in modifications or retrieval of information from the knowledge bases. All of the GKB-Editor's knowledge access and modification functionality has been developed using this GFP. As a direct result, the GKB-Editor will be immediately compatible with those FRSs for which the FRS-specific methods that implement the protocol have been defined, and extensible to the other FRSs.
Motivation
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There are several reasons for wanting to to develop a generic browsing
and editing tool for accessing and modifying knowledge stored in
FRSs. At present, and for the foreseeable future, the knowledge that a
developer or user wants/needs to access will not be in a common
representation language or system. Yet it is impractical for any
single developer or user to become familiar with every different
knowledge representation system. Further, many of these systems do not
provide a user-friendly means to access and edit their knowledge: some
systems provide only the equivalent of subroutine calls; some provide
graphical portrayals of stored knowledge but still resort to
subroutines for editing; few provide editing capabilities through
direct pictorial manipulation; those that do provide direct pictorial
manipulation do so in incompatible ways.
The past approach of developing knowledge editors and browsers that were tightly wedded to a single FRS is impractical. The substantial efforts required to create such tools become lost if the associated FRS falls into disuse. Since most FRSs share a common core functionality, a more cost-effective approach is to amortize the cost of developing FRS interface tools across a number of FRSs. Because the GKB-Editor communicates with knowledge base systems through the GFP, in order for FRS developers to take advantage of sophisticated browsing and editing capabilities, they need only provide a translation from their representation language to the language of the GFP. This task is considerably simpler that that of building a graphical interface from scratch. From the user's point of view, the GKB-Editor masks the representational details of the different underlying knowledge representation systems, presenting a common look-and-feel for all FRSs. A single intuitive interface can be used by domain experts to freely access, understand, utilize, or modify the knowledge stored under multiple frame systems.
Availability
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The GKB-Editor is currently available for testing in a beta release.
It runs on Lucid Common Lisp 4.1.1 with CLIM 1.1, and on Allegro
Common Lisp 4.2 with CLIM 2.0. It will run with
any FRS for which there is a GFP interface, and has been tested with
Loom 2.1 from
USC/ISI, with Theo from CMU, and with SIPE from SRI. To obtain the
GKB-Editor, see the Installation Instructions.