Page 102 - DCAP506_ARTIFICIAL_INTELLIGENCE

Artificial Intelligence

Notes  JTMS can symbolize P and P concurrently. An LTMS would throw a challenge here.
 If this happens network has to be reconstructed.

Assumption-based Truth Maintenance Systems (ATMS)

 JTMS and LTMS follow a single line of reasoning at a time and backtrack (dependency-
directed) when required — depth first search.

 ATMS sustain alternative paths in parallel — breadth-first search
 Backtracking is averted at the cost of sustaining numerous contexts.
 On the other hand as reasoning continues, disagreements occur and the ATMS can be
pruned
 Just find assertion with no suitable justification.

Task Make distinction between Justification-based Truth Maintenance Systems (JTMS)
and Logic-based Truth Maintenance Systems (LTMS).

Self Assessment

Fill in the blanks:
10. .............................. is a rule of speculation that permits you to come to the conclusion that
the objects you can demonstrate that posses some property, p, are actually all the objects
that posses that property.

11. In .............................., assertions are connected through a network of dependency.
12. .............................. is a simple TMS such that it does not recognize anything regarding the
structure of the assertions themselves.

13. .............................. is similar to JTMS except nodes (assertions) presume no relationships
between them except ones overtly specified in justifications.
14. JTMS and LTMS follow a .............................. line of reasoning at a time and backtrack
(dependency-directed) when required — depth first search.
15. .............................. sustain alternative paths in parallel — breadth-first search.

7.6 Summary

 When we need any knowledge system to accomplish something it has not been clearly
informed how to do, it must reason.
 In monotonic reasoning if we expand at set of axioms we cannot withdraw any present
declarations or axioms.
 Default reasoning is a very general from of non-monotonic reasoning where we want to
sketch conclusion based on what is most probable to be correct.

 Non-Monotonic reasoning is common depiction of a class of reasoning.
 Non-Monotonic Logic is fundamentally an extension of first-order predicate logic to
comprise a modal operator, M.

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