Cut sets as recognizable tree languages
نویسندگان
چکیده
A tree series over a semiring with partially ordered carrier set can be considered as a fuzzy set. We investigate conditions under which it can also be understood as a fuzzi ed recognizable tree language. In this sense, su cient conditions are presented which, when imposed, ensure that every cut set, i.e., the pre-image of a prime lter of the carrier set, is a recognizable tree language. Moreover, such conditions are also presented for cut sets of recognizable tree series.
منابع مشابه
On Recognizable Tree Languages Beyond the Borel Hierarchy
We investigate the topological complexity of non Borel recognizable tree languages with regard to the difference hierarchy of analytic sets. We show that, for each integer n ≥ 1, there is a Dωn(Σ 1 1)-complete tree language Ln accepted by a (non deterministic) Muller tree automaton. On the other hand, we prove that a tree language accepted by an unambiguous Büchi tree automaton must be Borel. T...
متن کاملA Note on Recognizable Sets of Unranked and Unordered Trees
Recognizable sets of unranked, unordered trees have been introduced in Courcelle [C89] in a Myhill-Nerode [N58] style of inverse homomorphisms of suitable finite magmas. This is equivalent of being the the union of some congruence classes of a congruence of finite index. We will add to the well-known concept of regular tree grammars a handling of nodes labeled with ǫ. With this rather unconvent...
متن کاملMultidimensional fuzzy finite tree automata
This paper introduces the notion of multidimensional fuzzy finite tree automata (MFFTA) and investigates its closure properties from the area of automata and language theory. MFFTA are a superclass of fuzzy tree automata whose behavior is generalized to adapt to multidimensional fuzzy sets. An MFFTA recognizes a multidimensional fuzzy tree language which is a regular tree language so that for e...
متن کاملGeneralized Tree-Adjoining Grammar
This paper continues a program extending results related to the descriptive characterization of the CFLs in terms of deenability in the weak monadic second-order theory of trees to the TALs and the entire hierarchy of Weir's Control Languages. Previously, we have shown that the languages in this hierarchy can be characterized by deenability in the weak monadic second-order theories of a general...
متن کاملRecognizability of Pomset Languages with Event Reenement
In the present paper, we contribute to the theory of recognizable pom-set (or partial word) languages from an algebraic point of view. By substitutions in pomsets labelled with variables and pomset contexts, we deene the syntactic equivalence of a pomset language, and use nite index ones to deene recognizable languages. We show that the induced recognizable pomset languages have extended closur...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Fuzzy Sets and Systems
دوره 157 شماره
صفحات -
تاریخ انتشار 2006