Some Algebras and Algorithms for Reasoning about Time and Space
نویسنده
چکیده
Constraint networks over relation algebras are deened. Compass algebras are introduced for reasoning about space. They are related to the interval algebras, which are used for reasoning about time. The problem of determining whether a network has a closed zeroless reduction is shown to NP-complete for almost all compass and interval algebras. This implies constraint satisfaction for these algebras is NP-complete. The following example shows how a particular compass algebra can be used to reason about space. the locations of the buildings.
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تاریخ انتشار 1990