This paper studies the computational complexity of disambiguation under probabilistic tree-grammars as in (Bod, 1992; Schabes and Waters, 1993). It presents a proof that the follo...
The terms of the upper and lower central series of a nilpotent computable group have computably enumerable Turing degree. We show that the Turing degrees of these terms are indepe...
Topological predicates between spatial objects have always been a main area of research on spatial data handling, reasoning, and query languages. The focus of research has definit...