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Mahmoud Raafat

Bio: Mahmoud Raafat is an academic researcher from Ain Shams University. The author has contributed to research in topics: Fuzzy logic & Universal set. The author has an hindex of 3, co-authored 6 publications receiving 22 citations.

Papers
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Journal ArticleDOI
01 Sep 2020
TL;DR: Two kinds of approximation operators via ideals which represent extensions of Pawlak’s approximation operator have been presented and the definitions of upper and lower approximations based on ideals have been given.
Abstract: The original model of rough sets was advanced by Pawlak, which was mainly involved with the approximation of things using an equivalence relation on the universal set of his approximation space. In this paper, two kinds of approximation operators via ideals which represent extensions of Pawlak’s approximation operator have been presented. In both kinds, the definitions of upper and lower approximations based on ideals have been given. Moreover, a new type of approximation spaces via two ideals which is called bi-ideal approximation spaces was introduced for the first time. This type of approximations was analyzed by two different methods, their properties are investigated, and the relationship between these methods is proposed. The importance of these methods was its dependent on ideals which were topological tools, and the two ideals represent two opinions instead of one opinion. At the end of the paper, an applied example had been introduced in the chemistry field by applying the current methods to illustrate the definitions in a friendly way.

17 citations

Journal ArticleDOI
01 Mar 2020
TL;DR: It is shown that how to apply the concept of hesitant fuzzy soft multisets in decision-making problems.
Abstract: In this paper, we introduce some important and basic issues of hesitant fuzzy soft multisets and present some results for hesitant fuzzy sets. The main results of the current branch are studied, and some of its structural properties are established such as the neighborhood hesitant fuzzy soft multisets, interior hesitant fuzzy soft multisets, hesitant fuzzy soft multi-topological spaces and hesitant fuzzy soft multi-basis. Therefore, we show that how to apply the concept of hesitant fuzzy soft multisets in decision-making problems.

4 citations

Journal ArticleDOI
TL;DR: It is shown that some results introduced in Girish and John (2011) are incorrect and a counterexample is given to confirm this claim.
Abstract: We show that some results introduced in Girish and John (2011) are incorrect. Moreover, a counterexample is given to confirm our claim. Furthermore, the correction form of the incorrect results in Girish and John (2011) is presented.

3 citations

Journal ArticleDOI
TL;DR: It is shown that [Lemma 3.3, p. 538] which was introduced in [1] is incorrect in general, by giving counter examples, and the correction form of the incorrect results in [2] is presented.

1 citations


Cited by
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Journal ArticleDOI
TL;DR: This paper generalizes three types of rough set models based on j-neighborhood space, and investigates some of their basic properties, and gives a comparison between the Yao’s approach and the authors' approach.
Abstract: In this paper, we generalize three types of rough set models based on j-neighborhood space (i.e, type 1 j-neighborhood rough set, type 2 j-neighborhood rough set, and type 3 j-neighborhood rough set), and investigate some of their basic properties. Also, we present another three types of rough set models based on j-adhesion neighborhood space (i.e, type 4 j-adhesion neighborhood rough set, type 5 j-adhesion neighborhood rough set, and type 6 j-adhesion neighborhood rough set). The fundamental properties of approximation operators based on j-adhesion neighborhood space are established. The relationship between the properties of these types is explained. Finally, according to j-adhesion neighborhood space, we give a comparison between the Yao’s approach and our approach.

38 citations

Journal ArticleDOI
TL;DR: The main contribution of the present article is to introduce a modification and a generalization for Feng's approximations, namely, soft β -rough approxIMations, and some of their properties will be studied.
Abstract: Soft rough set theory has been presented as a basic mathematical model for decision-making for many real-life data However, soft rough sets are based on a possible fusion of rough sets and soft sets which were proposed by Feng et al [20] The main contribution of the present article is to introduce a modification and a generalization for Feng's approximations, namely, soft β -rough approximations, and some of their properties will be studied A comparison between the suggested approximations and the previous one [20] will be discussed Some examples are prepared to display the validness of these proposals Finally, we put an actual example of the infections of coronavirus (COVID-19) based on soft β -rough sets This application aims to know the persons most likely to be infected with COVID-19 via soft β -rough approximations and soft β -rough topologies [ABSTRACT FROM AUTHOR] Copyright of Turkish Journal of Mathematics is the property of Scientific and Technical Research Council of Turkey and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission However, users may print, download, or email articles for individual use This abstract may be abridged No warranty is given about the accuracy of the copy Users should refer to the original published version of the material for the full abstract (Copyright applies to all Abstracts )

27 citations

Journal ArticleDOI
TL;DR: In this paper , the authors introduce a topological method to produce new rough set models based on the idea of "somewhat open sets" which is one of the celebrated generalizations of open sets.
Abstract: Abstract In this paper, we introduce a topological method to produce new rough set models. This method is based on the idea of “somewhat open sets” which is one of the celebrated generalizations of open sets. We first generate some topologies from the different types of $$N_\rho $$ N ρ -neighborhoods. Then, we define new types of rough approximations and accuracy measures with respect to somewhat open and somewhat closed sets. We study their main properties and prove that the accuracy and roughness measures preserve the monotonic property. One of the unique properties of these approximations is the possibility of comparing between them. We also compare our approach with the previous ones, and show that it is more accurate than those induced from open, $$\alpha $$ α -open, and semi-open sets. Moreover, we examine the effectiveness of the followed method in a problem of Dengue fever. Finally, we discuss the strengths and limitations of our approach and propose some future work.

23 citations

Journal ArticleDOI
Mona Hosny1
01 Jan 2020-Filomat
TL;DR: This work concentrates on generating different topologies by using the concept of the ideal to remove the vagueness of a concept to uncertainty areas at their borders by increasing the lower approximation and decreasing the upper approximation.
Abstract: The current work concentrates on generating different topologies by using the concept of the ideal. These topologies are used to make more thorough studies on generalized rough set theory. The rough set theory was first proposed by Pawlak in 1982. Its core concept is upper and lower approximations. The principal goal of the rough set theory is reducing the vagueness of a concept to uncertainty areas at their borders by increasing the lower approximation and decreasing the upper approximation. For the mentioned goal, different methods based on ideals are proposed to achieve this aim. These methods are more accurate than the previous methods. Hence it is very interesting in rough set context for removing the vagueness (uncertainty).

22 citations

Journal ArticleDOI
TL;DR: New approximations are proposed representing an extension of Pawlak’s rough sets and some of their generalizations, where the precision of these approximation is substantially improved and a medical application of lung cancer disease is given.
Abstract: Approximation space can be said to play a critical role in the accuracy of the set’s approximations. The idea of “approximation space” was introduced by Pawlak in 1982 as a core to describe informa...

20 citations