Extended Multi Bottom-Up Tree Transducers Composition and Decomposition
نویسندگان
چکیده
Extended multi bottom-up tree transducers are de ned and investigated. They are an extension of multi bottom-up tree transducers by arbitrary, not just shallow, left-hand sides of rules; this includes rules that do not consume input. It is shown that such transducers, even linear ones, can compute all transformations that are computed by linear extended top-down tree transducers, which are a theoretical model for syntax-based machine translation. Moreover, the classical composition results for bottom-up tree transducers are generalized to extended multi bottom-up tree transducers. Finally, characterizations in terms of extended top-down tree transducers and tree bimorphisms are presented.
منابع مشابه
Composition and Decomposition of Extended Multi Bottom-Up Tree Transducers?
Extended multi bottom-up tree transducers are de ned and investigated. They are an extension of multi bottom-up tree transducers by arbitrary, not just shallow, left-hand sides of rules; this includes rules that do not consume input. It is shown that such transducers can compute all transformations that are computed by linear extended top-down tree transducers (which are a theoretical model for...
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