73 research outputs found
Two characterisation results of multiple context-free grammars and their application to parsing
In the first part of this thesis, a Chomsky-SchĂŒtzenberger characterisation and an automaton characterisation of multiple context-free grammars are proved. Furthermore, a framework for approximation of automata with storage is described. The second part develops each of the three theoretical results into a parsing algorithm
New Results on Context-Free Tree Languages
Context-free tree languages play an important role in algebraic semantics and are applied in mathematical linguistics. In this thesis, we present some new results on context-free tree languages
Equivalence Problems for Tree Transducers: A Brief Survey
The decidability of equivalence for three important classes of tree
transducers is discussed. Each class can be obtained as a natural restriction
of deterministic macro tree transducers (MTTs): (1) no context parameters,
i.e., top-down tree transducers, (2) linear size increase, i.e., MSO definable
tree transducers, and (3) monadic input and output ranked alphabets. For the
full class of MTTs, decidability of equivalence remains a long-standing open
problem.Comment: In Proceedings AFL 2014, arXiv:1405.527
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