Composition for Cardinal Directions by Decomposing Horizontal and Vertical Constraints
Ah-Lian Kor, Brandon Bennett · Leeds Beckett Repository (Leeds Beckett University) · 2003
In this paper, we demonstrate how to group the nine cardi-nal directions into sets and use them to compute a composi-tion table. Firstly, we define each cardinal direction in terms of a certain set of constraints. This is followed by decom-posing the cardinal directions into sets corresponding to the horizontal and vertical constraints. We apply two different techniques to compute the composition of these sets. The first technique is an algebraic computation while the second is the typical technique of reasoning with diagrams. The ratio-nale of applying the latter is for confirmation purposes. The use of typical composition tables for existential inference is rarely demonstrated. Here, we shall demonstrate how to use the composition table to answer queries requiring the com-mon forward reasoning as well as existential inference.Also, we combine mereological and cardinal direction relations to create a hybrid model which is more expressive.