no code implementations • 1 Jun 2015 • Zhiguo Long, Sanjiang Li
This paper first gives a characterisation of distributive subalgebras, which states that the intersection of a set of $n\geq 3$ relations in the subalgebra is nonempty if and only if the intersection of every two of these relations is nonempty.
no code implementations • 3 Mar 2014 • Sanjiang Li, Zhiguo Long, Weiming Liu, Matt Duckham, Alan Both
In this paper, we show that this problem is in general intractable, but becomes tractable if $\Gamma$ is over a tractable subalgebra $\mathcal{S}$ of a qualitative calculus.