The aim of this paper is the study of trapezoidal approximation operators, preserving more indicators of fuzzy numbers, relationships between them and their applications. Initial results lead to achieve three main tra...
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The aim of this paper is the study of trapezoidal approximation operators, preserving more indicators of fuzzy numbers, relationships between them and their applications. Initial results lead to achieve three main trapezoidal approximation operators that one of them preserves the core, value and the ambiguity, and another one preserves the core and the expected interval, and third operator preserves the value, ambiguity and expected interval. The related concepts and the important properties of these operators and also, comparisons between them are brought, in details. Finally, a ranking method, an approximation operator preserving the most indicators of fuzzy numbers, and a trapezoidal approximation algorithm with its advantages and comparative examples are given as practical applications of the obtained results.
In this paper axiomatic characterizations of relation-based intuitionistic fuzzy rough approximation operators determined by an intuitionistic fuzzy triangular norm T and its dual intuitionistic fuzzy triangular conor...
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In this paper axiomatic characterizations of relation-based intuitionistic fuzzy rough approximation operators determined by an intuitionistic fuzzy triangular norm T and its dual intuitionistic fuzzy triangular conorm S on [0,1]x[0,1] are proposed. The constructive definitions and properties of S-lower and T-upper intuitionistic fuzzy rough approximation operators are first introduced. Operator-oriented characterizations of (S,T)-intuitionistic fuzzy rough approximation operators are then explored. Different sets of independent axioms for characterizing the essential properties of (S,T)-intuitionistic fuzzy rough approximation operators generated by various intuitionistic fuzzy relations are presented. Finally, it is examined that these sets of axioms can all be replaced by single axioms.
This paper presents a general framework for the study of (I,N)-single valued neutrosophic rough sets from constructive and axiomatic perspectives. In the constructive approach, a pair of single valued neutrosophic rou...
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This paper presents a general framework for the study of (I,N)-single valued neutrosophic rough sets from constructive and axiomatic perspectives. In the constructive approach, a pair of single valued neutrosophic rough approximation operators based on single valued neutrosophic implicator I and single valued neutrosophic norm N is first proposed. Moreover, some basic properties of (I,N)-single valued neutrosophic rough approximation operators are explored. In addition, connections between single valued neutrosophic relations and (I,N)-single valued neutrosophic rough approximation operators are systematically discussed. In the axiomatic approach, axiomatic characterization of (I,N)-single valued neutrosophic approximation operators is studied. Specifically, different axiom sets characterizing the intrinsic properties of (I,N)-single valued neutrosophic rough approximation operators associated with diverse single valued neutrosophic relations are investigated in detail.
Axiomatic characterization of approximation operators plays an important role in the study of rough set theory. Different axiom sets of abstract operators can illustrate different classes of rough set systems. In this...
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Axiomatic characterization of approximation operators plays an important role in the study of rough set theory. Different axiom sets of abstract operators can illustrate different classes of rough set systems. In this paper, we are devoted to searching for a single axiom to characterize L-fuzzy rough approximation operators based on residuated lattices. Axioms of L-fuzzy set theoretic operators make sure of the existence of certain types of L-fuzzy relations which produce the same operators. We demonstrate that the lower (upper) L-fuzzy rough approximation operators generated by a generalized L-fuzzy relation can be characterized by only one axiom. Furthermore, we also use one axiom to characterize L-fuzzy rough approximation operators produced by the L-fuzzy serial, reflexive, symmetric and T-transitive relations as well as any of their compositions. (c) 2017 Elsevier B.V. All rights reserved.
We present a new collection of upper approximation operators for covering based rough sets, obtained from sub modular functions and closure operators. Each non decreasing submodular function defines a closure operator...
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ISBN:
(纸本)9783319608372;9783319608365
We present a new collection of upper approximation operators for covering based rough sets, obtained from sub modular functions and closure operators. Each non decreasing submodular function defines a closure operator that can be considered as an approximation operator. The construction allows us to define several upper approximation operators. Some properties of these operators are studied.
In the recent article "On some types of covering rough sets from topological points of view" [14], the author develops a topological approach to covering-based rough sets. In this context, a number of corres...
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In the recent article "On some types of covering rough sets from topological points of view" [14], the author develops a topological approach to covering-based rough sets. In this context, a number of corresponding approximation operators are introduced, their inclusion relationships are verified, and various conditions under which the operators coincide are proven. On the other hand, a lot of effort has recently been dedicated by several authors to study covering-based approximation operators within a general framework of dual approximation operators [2,3,7-10,12]. In this note, we study correspondences between the framework of Zhao and the framework established in [2]. In particular, we evaluate how the newly introduced topological approximation operators relate to existing ones in terms of equalities and partial order relations. (C) 2017 Elsevier Inc. All rights reserved.
The axiomatic approach is more appropriate than constructive approach for studying the algebraic structure of rough sets. In this paper, the more simple axiomatic characterizations of (theta, sigma)-fuzzy rough approx...
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The axiomatic approach is more appropriate than constructive approach for studying the algebraic structure of rough sets. In this paper, the more simple axiomatic characterizations of (theta, sigma)-fuzzy rough approximation operators are explored where u is a residuated implicator and sigma is its dual implicator. Firstly, we review the existing independent axiomatic sets to characterize various types of 19-lower and a-upper fuzzy rough approximation operators. Secondly, we present one-axiom characterizations of (theta, sigma)-fuzzy rough approximation operators constructed by a serial fuzzy relation on two universes. Furthermore, we show that (theta, sigma)-fuzzy rough approximation operators, corresponding to reflexive, symmetric and T-transitive fuzzy relations, can be presented by only two axioms respectively. We conclude the paper by introducing some potential applications and future works.
Axiomatic characterizations of approximation operators are of importance in the study of rough set theory. In this paper axiomatic characterizations of relation-based (S, T)-fuzzy rough approximation operators are inv...
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Axiomatic characterizations of approximation operators are of importance in the study of rough set theory. In this paper axiomatic characterizations of relation-based (S, T)-fuzzy rough approximation operators are investigated. By employing a triangular conorm S and a triangular norm T on [0, 1], we first introduced the constructive definitions of S-lower and T-upper fuzzy rough approximation operators with their essential properties. We then propose an operator-oriented characterization of (S, T)-fuzzy rough sets, that is, fuzzy set-theoretic operators defined by axioms guarantee the existence of different types of fuzzy relations which produce the same operators. We show that the S-lower (and, respectively, T-upper) fuzzy rough approximation operators generated by a generalized fuzzy relation can be described by only one axiom. We further show that (S, T)-fuzzy rough approximation operators corresponding to special types of fuzzy relations, such as serial, reflexive, symmetric, and T-transitive ones as well as any of their compositions, can also be characterized by single axioms. (C) 2015 Elsevier Inc. All rights reserved.
Axiomatic characterizations of approximation operators are important in the study of rough set theory. In this paper, axiomatic characterizations of relation-based fuzzy rough approximation operators determined by a f...
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Axiomatic characterizations of approximation operators are important in the study of rough set theory. In this paper, axiomatic characterizations of relation-based fuzzy rough approximation operators determined by a fuzzy implication operator I are investigated. We first review the constructive definitions and properties of lower and upper I-fuzzy rough approximation operators. We then propose an operator-oriented characterization of I-fuzzy rough sets. We show that the lower and upper I-fuzzy rough approximation operators generated by an arbitrary fuzzy relation can be described by single axioms. We further examine that I-fuzzy rough approximation operators corresponding to some special types of fuzzy relations, such as serial, reflexive, and T -transitive ones, can also be characterized by single axioms.
Axiomatic characterizations of approximation operators are important in the study of rough set theory. In this paper, axiomatic characterizations of relation-based intuitionistic fuzzy rough approximation operators de...
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ISBN:
(纸本)9783319257839;9783319257822
Axiomatic characterizations of approximation operators are important in the study of rough set theory. In this paper, axiomatic characterizations of relation-based intuitionistic fuzzy rough approximation operators determined by an intuitionistic fuzzy implication operator I are investigated. We present a set of axioms of lower/upper I-intuitionistic fuzzy set-theoretic operator which is necessary and sufficient for the existence of an intuitionistic fuzzy relation producing the same operator. We show that the lower and upper I-intuitionistic fuzzy rough approximation operators generated by an arbitrary intuitionistic fuzzy relation can be described by single axioms. Moreover, the I-intuitionistic fuzzy rough approximation operators generated by reflexive and T-transitive intuitionistic fuzzy relations can also be characterized by single axioms.
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