Cover vol. 12, no. 1, February 2015
text
article
2015
eng
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
0
http://ijfs.usb.ac.ir/article_2650_59e18134e188eee79afb2e07d9f951f0.pdf
dx.doi.org/10.22111/ijfs.2015.2650
An integrated multi-criteria decision-making methodology based on type-2 fuzzy sets for selection among energy alternatives in Turkey
Melike
Erdogan
Department of Industrial Engineering, Yildiz Technical University, Yildiz, BESIKTAS, Istanbul, Turkey
author
ihsan
Kaya
Department of Industrial Engineering, Yildiz Technical University, Yildiz, BESIKTAS, Istanbul, Turkey
author
text
article
2015
eng
Energy is a critical factor to obtain a sustainable development for countries and governments. Selection of the most appropriate energy alternative is a completely critical and a complex decision making problem. In this paper, an integrated multi-criteria decision-making (MCDM) methodology based on type-2 fuzzy sets is proposed for selection among energy alternatives. Then a roadmap has been created for Turkey.To overcome uncertainties in decision making process, the fuzzy set theory (FST) is suggested.For this aim, two of the most known MCDM methodologies are reconsidered by using type-2 fuzzy sets.Fuzzy Analytic Hierarchy Process (FAHP) based on interval type-2 fuzzy sets is constructed and is used to obtain the weights of the criteria affecting energy alternatives. To rank the energy alternatives, the other MCDM method that is Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is fuzzified by interval type-2 fuzzy sets. The proposed integrated MCDM methodology based on interval type-2 fuzzy sets is applied to obtain a road map of energy policies for Turkey.
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
1
25
http://ijfs.usb.ac.ir/article_1839_d23c7ca7b9fd0dade01c8ab6932814d4.pdf
dx.doi.org/10.22111/ijfs.2015.1839
Approximation theorems for fuzzy set multifunctions in Vietoris topology. Physical implications of regularity
A.
Gavrilut
Faculty of Mathematics, \Alexandru Ioan Cuza" University of Iasi
Iasi, Romania
author
M.
Agop
Department of Physics, Gheorghe Asachi Technical University of Iasi, Iasi,
Romania
author
text
article
2015
eng
n this paper, we consider continuity properties(especially, regularity, also viewed as an approximation property) for $%mathcal{P}_{0}(X)$-valued set multifunctions ($X$ being a linear,topological space), in order to obtain Egoroff and Lusin type theorems forset multifunctions in the Vietoris hypertopology. Some mathematicalapplications are established and several physical implications of themathematical model of regularity are presented, which allows aclassification of the physical models.
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
27
42
http://ijfs.usb.ac.ir/article_1840_855de66e0a5045c0650164221c4a2935.pdf
dx.doi.org/10.22111/ijfs.2015.1840
Uniformities in fuzzy metric spaces
Yueli
Yue
Department of Mathematics, Ocean University of China, 238 Songling
Road, 266100, Qingdao, P.R.China
author
Jinming
Fang
Department of Mathematics, Ocean University of China, 238 Songling
Road, 266100, Qingdao, P.R.China
author
text
article
2015
eng
The aim of this paper is to study induced (quasi-)uniformities in Kramosil and Michalek's fuzzy metric spaces. Firstly, $I$-uniformity in the sense of J. Guti'{e}rrez Garc'{i}a and $I$-neighborhood system in the sense of H"{o}hle and u{S}ostak are induced by the given fuzzy metric. It is shown that the fuzzy metric and the induced $I$-uniformity will generate the same $I$-neighborhood system. Secondly, the relationship between Hutton quasi-uniformities and $I$-quasi-uniformities is given and it is proved that the category of strongly stratified $I$-quasi-uniform spaces can be embedded in the category of Hutton quasi-uniform spaces as a bicoreflective subcategory. Also it is shown that two kinds of Hutton quasi-uniformities can generate the same $I$-uniformity in fuzzy metric spaces.
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
43
57
http://ijfs.usb.ac.ir/article_1841_934512989c8d6bed65891801d995c6a2.pdf
dx.doi.org/10.22111/ijfs.2015.1841
Application of parametric form for ranking of fuzzy numbers
R.
Ezzati
Department of Mathematics, Karaj Branch, Islamic Azad University, 31485 - 413, Karaj, Iran
author
S.
Khezerloo
Department of Mathematics, Islamic Azad University - South Tehran, Branch, Tehran, Iran
author
S.
Ziari
Department of Mathematics, Firoozkooh Branch,Islamic Azad University, Firoozkooh, Iran
author
text
article
2015
eng
In this paper, we propose a new approach for ranking all fuzzynumbers based on revising the ranking method proposed by Ezzati et al. cite{Ezzati}.To this end, we present and investigate some properties of the proposed approach indetails. Finally, to illustrate the advantage of the proposed method, it is applied to several groups of fuzzy numbers and the results are compared with other related and familiar ones.
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
59
74
http://ijfs.usb.ac.ir/article_1842_27cb3eea8770ed442d2b473b328b2217.pdf
dx.doi.org/10.22111/ijfs.2015.1842
Coupled Coincidence and Common Fixed Point Theorems for Single-Valued and Fuzzy Mappings
Li
Zhu
Department of Mathematics, Nanchang University, Nanchang 330031, P.
R. China And Department of Mathematics, Jiangxi Agricultural University, Nanchang
330045, P. R. China
author
Chuanxi
Zhu
Department of Mathematics, Nanchang University, Nanchang 330031,
P. R. China
author
Xianjiu
Huang
Department of Mathematics, Nanchang University, Nanchang 330031,
P. R. China
author
text
article
2015
eng
In this paper, we study the existence of coupled coincidence andcoupled common fixed points for single-valued and fuzzy mappingsunder a contractive condition in metric space. Presented theoremsextend and improve the main results of Abbas and$acute{C}$iri$acute{c}$ {itshape et al.} [M. Abbas, L.$acute{C}$iri$acute{c}$, {itshape et al.}, Coupled coincidenceand common fixed point theorems for hybrid pair of mappings, FixedPoint Theory Appl. (4) (2012) doi:10.1186/1687-1812-2012-4].
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
75
87
http://ijfs.usb.ac.ir/article_1862_0c9a4b14e5a54b07a78dac040c0e304f.pdf
dx.doi.org/10.22111/ijfs.2015.1862
Minimal solution of fuzzy linear systems
M.
Otadi
Department of Mathematics, Firoozkooh Branch, Islamic Azad Univer-
sity, Firoozkooh, Iran
author
M.
Mosleh
Department of Mathematics, Firoozkooh Branch, Islamic Azad Univer-
sity, Firoozkooh, Iran
author
text
article
2015
eng
In this paper, we use parametric form of fuzzy number and we converta fuzzy linear system to two linear system in crisp case. Conditions for the existence of a minimal solution to $mtimes n$ fuzzy linear equation systems are derived and a numerical procedure for calculating the minimal solution is designed. Numerical examples are presented to illustrate the proposed method.
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
89
99
http://ijfs.usb.ac.ir/article_1863_1b8410b23769ca1ff9adc789b590ebb0.pdf
dx.doi.org/10.22111/ijfs.2015.1863
On upper and lower almost weakly continuous fuzzy multifunctions
S. E.
Abbas
Department of Mathematics, Faculty of Science, Jazan University, Saudi
Arabia
author
M. A.
Hebeshi
Department of Mathematics, Faculty of Science, Sohag University,
Egypt
author
I. M.
Taha
Department of Mathematics, Faculty of Science, Sohag University,
Egypt
author
text
article
2015
eng
The aim of this paper is to introduce the concepts of fuzzy upper and fuzzy lower almost continuous, weakly continuous and almost weakly continuous multifunctions. Several characterizations and properties of these multifunctions along with their mutual relationships are established in $L$-fuzzy topological spaces
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
101
114
http://ijfs.usb.ac.ir/article_1864_eefebf9043466cbd4a7fffd52e7d586e.pdf
dx.doi.org/10.22111/ijfs.2015.1864
Fuzzy Vector Equilibrium Problem
Mijanur
Rahaman
Department of Mathematics, Aligarh Muslim University, Aligarh-
202002, India
author
Rais
Ahmad
Department of Mathematics, Aligarh Muslim University, Aligarh-202002,
India
author
text
article
2015
eng
In the present paper, we introduce and study a fuzzy vector equilibrium problem and prove some existence results with and without convexity assumptions by using some particular forms of results of textit{Kim} and textit{Lee} [W.K. Kim and K.H. Lee, Generalized fuzzy games and fuzzy equilibria, Fuzzy Sets and Systems, 122 (2001), 293-301] and textit{Tarafdar} [E. Tarafdar, Fixed point theorems in $H$-spaces and equilibrium points of abstract economies, J. Aust. Math. Soc.(Series A), 53(1992), 252-260]. An example is also constructed in support of fuzzy vector equilibrium problem.
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
115
122
http://ijfs.usb.ac.ir/article_1865_534c7c77c8a3bbb244c81ad089b2ba68.pdf
dx.doi.org/10.22111/ijfs.2015.1865
Generalized Weakly Contractions in Partially Ordered Fuzzy Metric Spaces
S. M.
Vaezpour
Department of Mathematics and Computer Science, Amirkabir Uni-
versity of Technology, 424 Hafez Avenue, Tehran 15914, Iran
author
S.
Vaezzadeh
Department of Mathematics and Computer Science,, Amirkabir University of Technology, 424 Hafez Avenue, Tehran 15914, Iran
author
text
article
2015
eng
In this paper, a concept of generalized weakly contraction mappings in partially ordered fuzzy metric spaces is introduced and coincidence point theorems on partially ordered fuzzy metric spaces are proved. Also, as the corollary of these theorems, some common fixed point theorems on partially ordered fuzzy metric spaces are presented.
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
123
129
http://ijfs.usb.ac.ir/article_1866_7f6476dc4b3ff67400972d3c18b7a46c.pdf
dx.doi.org/10.22111/ijfs.2015.1866
Persian-translation vol. 12, no. 1, February 2015
text
article
2015
eng
Iranian Journal of Fuzzy Systems
University of Sistan and Baluchestan
1735-0654
12
v.
1
no.
2015
133
141
http://ijfs.usb.ac.ir/article_2651_15ce1ae24f3cd06bf99f720897fdd3a3.pdf
dx.doi.org/10.22111/ijfs.2015.2651