We study the expressiveness of a positive fragment of path queries, denoted Path+ , on node-labeled trees documents. The expressiveness of Path+ is studied from two angles. First, ...
Yuqing Wu, Dirk Van Gucht, Marc Gyssens, Jan Pared...
Uniqueness of normal forms (UN= ) is an important property of term rewrite systems. UN= is decidable for ground (i.e., variable-free) systems and undecidable in general. Recently ...
- There is continuing research interest in comparison of the complexity of problems within the class NP-Complete. This paper examines the representational power of conjunctive norm...
In this note, we prove that having unique head-normal forms is a sufficient condition on partial combinatory algebras to be completable. As application,we show that the pca of str...
We describe the formalisation of the normal forms of context-free grammars (CFGs) using the HOL4 theorem prover. These straightforward pen and paper proofs easily understood from t...