The process employed by addam first creates a new

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The process employed by ADDAM first creates a new disassembly plan and thenexecutes that plan. Planning in ADDAM is adaptive; it consists of taking an existingplan for disassembling a similar device and adapting it into a plan for the new device.ADDAM’s method for planning constructs a mapping between elements of the newand existing devices, converts portions of the plan for the existing device intoanalogous portions of the plan for the new device, and then converts the orderingdependencies for the existing plan into analogous ordering dependencies for thenew plan.5. Meta-case-based reasoning processIf a user asks REM to perform a task, such as assembling a device, REM first checksto see whether that task already has an existing implementation (i.e. a method or aprimitive implementation). If it does not, then REM needs to employ its meta-case-based reasoning process to adapt its existing knowledge to satisfy the require-ments of the task. That process involves (a) retrieving an existing task that has amethod and is similar to the desired task, (b) adapting a method for the retrievedtask to implement the desired task, (c) verifying that the adapted method doesaccomplish the desired effect by executing the desired task with that method, and(d) storing the adapted method for future use when the same task is encountered andfor future adaptation when another similar task is encountered.5.1RetrievalAs described in section 3.3, REM uses Loom as its mechanism for storing andaccessing knowledge. To retrieve an existing task that is similar to some specifiedtask, REM issues a Loom query asking for any task that has a method for which thesimilar-to relationholds with the specified task.Loom decides whether a relation holds in two ways: it may have an explicitassertion in memory indicating that the relation holds, or it may use an inference rule(i.e. a statement that some conditionimpliesthat the relation holds). As noted insection3.3,REMincludessomedomain-independentrulesforinferringthesimilar-torelation. For example, REM has a rule which states that tasks whichhave similar effects are similar to each other. It determines that tasks have similareffects if they meet the following requirements:.they have the same sets of parameters,.andthey have similargivenconditions,Meta-case-based reasoning: self-improvement through self-understanding11
Downloaded By: [Georgia Technology Library] At: 14:13 11 June 2008 .andthey have similarmakesconditions.Conditions (i.e. logical expressions encoded in the Loom syntax) condition areidentified as similar if they meet the following requirements:.they are equal,.orthey both have the form (<operator> <subexpression>...),andtheoperators (e.g. :and, :or, :not) are identical,andeach sub-expression in one issimilar to the corresponding subexpression in the other one,.

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