Abstract: An expert system, such as could be used for service of a complicated physical device such as a printer or copier, exploits a knowledge base which is written in a markup language format such as SGML. The knowledge base comprises text which, if desired, can be printed out on paper to yield a traditional service manual. In addition to the typical formatting markup language tags surrounding the text of the knowledge base, hierarchical tags are provided in the electronic version of the knowledge base, to define a set of decision trees which can be accessed and navigated by an expert system. A diagnostic advisor can access specific elements of the knowledge base as needed to synthesize optimized diagnosis and repair procedures depending on an entry given by a tech rep servicing a machine. This arrangement thus supports both a printed service manual and a viewer that provides expert diagnostic advice.

Abstract: Method and apparatus of accessing and displaying hierarachical files on an electronic workstation screen that includes: (1) an Open Next-To operation that opens a separate window for a file to prevent the window from which the file was originally opened from being obscured, (2) a combination of both Open Next-To and Open-Within operations for opening different combinations, (3) "Chording" for displaying general options and depth display options to give the user a choice of a window OPEN method and hierarchical display depth as well as a choice of selecting "display all levels" format, (4) a FIND capability that enables finding of strings in a folder display, including forward and backward search and automatic text type conversion based on selection, (5) Iconic Pretty-Printing, that is, the icon optionally combined with text is offset as a function of its depth in a hierarchy including, (6) Folding of the display when the indentation reaches a desired column width, (7) a visual method of indicating the extent