3 A Meta-Logic for Unification 4 3.1 A First-Order Unification Logic with Quantifier Dependencies . . . . . . . . . . . . . 5 3.2 Transformations for First-Order Unification . . . . . . . . . . . . . . . . . . . . . . . 6 3.3 A Unification Logic for LF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.4 A Generalization of Lλ Unification to LF . . . . . . . . . . . . . . . ....

We extend order-sorted unification by permitting regular expression sorts for variables and in the domains of function symbols. The obtained signature corresponds to a finite bottom-up unranked tree automaton. We prove that regular expression order-sorted (REOS) unification is of type infinitary and decidable. The unification problem presented by us generalizes some known problems, such as, e.g...

Both Sequence and Context Unification generalize the same problem: Word Unification. Besides that, Sequence Unification solves equations between unranked terms involving sequence variables, and seems to be appealing for information extraction in XML documents, program transformation, knowledge representation, and rule-based programming. It is decidable. Context Unification deals with the same p...

Unification of (typed) feature structures is an important tool for capturing linguistic generalizations. It is the core of a family of linguistic formalisms, it has been applied in phonology, morphology, syntax, and semantics, and is dominant in most linguistically informed work in natural language processing. Unification monotonically merges information. Default unification provides a non-mono...

Classical unification is strict in the sense that it requires a perfect agreement between the terms being unified. In practice, data is seldom error-free and can contain inconsistent information. Classical unification fails when the data is imperfect. Fuzzy unification partially addresses uncertainty but requires the creation of fuzzy databases. We propose the Theory of Relaxed Unification as a...

Among the different processes that entail unification-based grammar parsing, the unification of feature structures is by far the most expensive one in terms of execution time. Unification of the feature structures of a given sentence typically takes between 85 and 98 per cent of the total elapsed time during parsing, thus the need to develop faster unification methods. The approach presented in...

Both Sequence and Context Unification generalize the same problem: Word Unification. Besides that, Sequence Unification solves equations between unranked terms involving sequence variables, and seems to be appealing for information extraction in XML documents, program transformation, knowledge representation, and rule-based programming. It is decidable. Context Unification deals with the same p...