Regular tree languages and quasi orders
نویسنده
چکیده
Regular languages were characterized as sets closed with respect to monotone well-quasi orders. A similar result is proved here for tree languages. Moreover, families of quasi orders that correspond to positive varieties of tree languages and varieties of finite ordered algebras are characterized.
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ورودعنوان ژورنال:
- Acta Cybern.
دوره 17 شماره
صفحات -
تاریخ انتشار 2006