This paper presents the Constraint Language for Lambda Structures (CLLS), a first-order
language for semantic underspecification thatconservatively extends dominance constraints …

We study the complexity and expressive power of conjunctive queries over unranked
labeled trees represented using a variety of structure relations such as “child”,“descendant” …

Contexts are terms with one 'hole', ie a place in which we can substitute an argument. In
context unification we are given an equation over terms with variables representing contexts …

Context unification is a variant of second‐order unification and also a generalization of string
unification. Currently it is not known whether context unification is decidable. An expressive …

Context unification is a natural variant of second-order unification that represents a
generalization of word unification at the same time. While second-order unification is well …

It is well-known that first order unification is decidable, whereas second order (and higher-
order) unification is undecidable. Bounded second order unification is second order …

Term unification plays an important role in many areas of computer science, especially in
those related to logic. The universal mechanism of grammar-based compression for terms …

The purpose of this paper is to describe a decision algorithm for unifiability of equations wrt
the equational theory D of two distributive axioms: x∗(y+ z)= x∗ y+ x∗ z and (x+ y)∗ z= x∗ …

Abstract Linear Second-Order Unification and Context Unification are closely related
problems. However, their equivalence was never formally proved. Context unification is a …

Abstract Bounded Second-Order Unification is a decidable variant of undecidable Second-
Order Unification. Stratified Context Unification is a decidable restriction of Context …