How to select an existing KB or create a new KB

The first step to using Chimaera is to select an existing KB or create a new one to work on. KBs of any loaded OKBC KB-type can be handled by the Chimaera tool. The KB selection dialogue is split into two key parts shown in the figure below:

The top part is used to create a new KB.

The KB you create must be one of the KB types known to Chimaera. The KB type is selected from the menu labeled "Create a new KB of this type:".

The bottom part is used to select an existing KB.

The KB you select can be either one that is currently loaded or one that is to be loaded from the library. Select a row from the table according to the KB you want to use. Note that different KB types will in general share different libraries, so the KBs that you will be offered to select or load will be different for each KB type. Once you have made your selection, Chimaera will load the selected KB if necessary and take you to the main working space of Chimaera.

In this tutorial, you will create a new KB. As shown below, select "Ontolingua" from the "Create a new KB of this type:" menu. Notice that this menu is spring-loaded, as are most of the menus in Chimaera. When you click on "Ontolingua", your selection will be computed after you have released the mouse button.

A blank form appears which you will use to input information about the KB that you are creating. The name of the new KB will be "kb-merge", and it will include the HPKB-Upper-Ontology. Type "kb-merge" into the "KB Name" box, and select "Hpkb-Upper-Level-Latest" from the "Parents" menu. Then, click the "Do it" button. Note: If you are using Ontolingua as the type of your new KB, you would generally use Frame-Ontology, not HPKB-Upper-Level-Latest, as a parent ontology.

You are now in the main working area of Chimaera. Because this KB is newly created, no classes are defined yet. Six command menus are available, but some commands are inactive. For a complete description of commands, you can click the ? (the help) on the right-top corner of the KB creation form. Notice that there are also command keys associated with many commands. The command key combination for activating a particular command is printed beside the command's entry in the menu.

In the next section, you will learn how to load a KB file into the newly created "KB-Merge".