...1.2.1

This work has taken place in the Qualitative Reasoning Group at the Artificial Intelligence Laboratory, The University of Texas at Austin. Research of the Qualitative Reasoning Group is supported in part by the Texas Advanced Research Program under grant no. 003658-175, NSF grants IRI-8905494 and IRI-8904454, and by NASA grant NAG 2-507.

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...Crawford

AI Principles Research Department, AT&T Bell Laboratories, Murray Hill, NJ 07974 (jc@research.att.com).

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...Kuipers

Department of Computer Sciences, The University of Texas At Austin, Austin, Texas 78712 (kuipers@cs.utexas.edu).

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...form.

The code in Algernon contains some heuristics for generating the ``internal form'' such that in many cases it is identical to the name of the frame. However, one should regard this as a happy coincidence when it happens and should not depend on it.

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...isa

The relation isa holds between an object and a set of which it is a member.

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...use.

The following slots are obsolete or for internal use only, and are not documented here: :decl-slots, :bind-to-values, :branch-on-values, :apply, :create.

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...pred.

Technical note: The partitions of pred are updated before pred is queried (or asserted), and the active partitions are updated after the operation on pred (see section 2.3.1).

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...rule.

Unlike some expert system shells in which every rule is applied whenever a new fact is asserted.

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