University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
29
Cove Vol.5, No.3, October 2008
0
EN
10.22111/ijfs.2008.2901
http://ijfs.usb.ac.ir/article_2901.html
http://ijfs.usb.ac.ir/article_2901_670fd9d88f16069bbcbb60c0052e20bf.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
08
OPTIMIZATION OF FUZZY CLUSTERING CRITERIA BY A HYBRID
PSO AND FUZZY C-MEANS CLUSTERING ALGORITHM
1
14
EN
E.
MEHDIZADEH
DEPARTMENT OF INDUSTRIAL ENGINEERING, SCIENCE & RESEARCH BRANCH,
ISLAMIC AZAD UNIVERSITY, TEHRAN, IRAN
mehdizadeh@qazviniau.ac.ir
S.
SADI-NEZHAD
DEPARTMENT OF INDUSTRIAL ENGINEERING, SCIENCE & RESEARCH BRANCH,
ISLAMIC AZAD UNIVERSITY, TEHRAN, IRAN
sadinejad@hotmail.com
R.
TAVAKKOLI-MOGHADDAM
DEPARTMENT OF INDUSTRIAL ENGINEERING, COLLEGE OF
ENGINEERING, UNIVERSITY OF TEHRAN, TEHRAN, IRAN
tavakoli@ut.ac.ir
10.22111/ijfs.2008.339
This paper presents an efficient hybrid method, namely fuzzy particleswarm optimization (FPSO) and fuzzy c-means (FCM) algorithms, to solve the fuzzyclustering problem, especially for large sizes. When the problem becomes large, theFCM algorithm may result in uneven distribution of data, making it difficult to findan optimal solution in reasonable amount of time. The PSO algorithm does find agood or near-optimal solution in reasonable time, but we show that its performancemay be improved by seeding the initial swarm with the result of the c-meansalgorithm. Various clustering simulations are experimentally compared with the FCMalgorithm in order to illustrate the efficiency and ability of the proposed algorithms.
Fuzzy clustering,Particle Swarm Optimization (PSO),Fuzzy
c-means (FCM)
http://ijfs.usb.ac.ir/article_339.html
http://ijfs.usb.ac.ir/article_339_3fd4baa8d09bbcf87e9f15a5e6ec363b.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
08
SOLVING FUZZY LINEAR SYSTEMS BY USING THE SCHUR
COMPLEMENT WHEN COEFFICIENT MATRIX IS AN
M-MATRIX
15
29
EN
M. S.
Hashemi
Department of Applied Mathematics,
Faculty of Mathematical Science, University of Tabriz, Tabriz-Iran
hashemi math396@yahoo.com
M. K.
Mirnia
Department of Applied Mathematics,
Faculty of Mathematical Science, University of Tabriz, Tabriz-Iran
mirnia-kam@tabrizu.ac.ir
S.
Shahmorad
Department of Applied Mathematics,
Faculty of Mathematical Science, University of Tabriz, Tabriz-Iran
shahmorad@tabrizu.ac.ir
10.22111/ijfs.2008.340
This paper analyzes a linear system of equations when the righthandside is a fuzzy vector and the coefficient matrix is a crisp M-matrix. Thefuzzy linear system (FLS) is converted to the equivalent crisp system withcoefficient matrix of dimension 2n × 2n. However, solving this crisp system isdifficult for large n because of dimensionality problems . It is shown that thisdifficulty may be avoided by computing the inverse of an n×n matrix insteadof Z^{−1}.
Fuzzy linear system,Schur complement,M-matrix,H-matrix
http://ijfs.usb.ac.ir/article_340.html
http://ijfs.usb.ac.ir/article_340_45018795472748406c9f0737e0cd837f.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
09
ALMOST S^{*}-COMPACTNESS IN L-TOPOLOGICAL SPACES
31
44
EN
Guo-Feng
Wen
School of Management Science and Engineering, Shandong Institute
of Business and Technology, Yantai 264005, P. R. China
wenguofeng@sdibt.edu.cn
Fu-Gui
Shi
Department of Mathematics, Beijing Institute of Technology, Beijing,100081,
P. R. China
fuguishi@bit.edu.cn
Hong-Yan
Li
School of Mathematics and Information Science, Shandong Institute
of Business and Technology, Yantai 264005, P. R. China
lihongyan@sdibt.edu.cn
10.22111/ijfs.2008.344
In this paper, the notion of almost S^{*}-compactness in L-topologicalspaces is introduced following Shi’s definition of S^{*}-compactness. The propertiesof this notion are studied and the relationship between it and otherdefinitions of almost compactness are discussed. Several characterizations ofalmost S^{*}-compactness are also presented.
L-topology,$\beta$_{a}-cover,Q_{a} -cover,S^{*}-compactness,Almost S^{*}-compactness
http://ijfs.usb.ac.ir/article_344.html
http://ijfs.usb.ac.ir/article_344_38806068a065c4d5b10248627da60caa.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
09
FUZZY ROUGH N-ARY SUBHYPERGROUPS
45
56
EN
Violeta Leoreanu
Fotea
Faculty of Mathematics, ”Al.I. Cuza” University, Street
Carol I, n.11, Iasi, Romania
leoreanu2002@yahoo.com
10.22111/ijfs.2008.345
Fuzzy rough n-ary subhypergroups are introduced and characterized.
Fuzzy rough n-ary subhypergroup,Fuzzy set,Rough set,n-ary subhypergroup
http://ijfs.usb.ac.ir/article_345.html
http://ijfs.usb.ac.ir/article_345_9c9774448c11be68582d02c4034ba721.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
09
BEST APPROXIMATION SETS IN -n-NORMED SPACE
CORRESPONDING TO INTUITIONISTIC FUZZY n-NORMED
LINEAR SPACE
57
69
EN
S.
Vijayabalaji
Department of Mathematics, Anna University, Tiruchirappallli,
Panruti Campus, Tamilnadu, India
balaji−nandini@rediffmail.com
N.
Thillaigovindan
Department of Mathematics, Annamalai university, Annamalainagar-
608002, Tamilnadu, India
thillai−n@sify.com
10.22111/ijfs.2008.346
The aim of this paper is to present the new and interesting notionof ascending family of $alpha $−n-norms corresponding to an intuitionistic fuzzy nnormedlinear space. The notion of best aproximation sets in an $alpha $−n-normedspace corresponding to an intuitionistic fuzzy n-normed linear space is alsodefined and several related results are obtained.
Fuzzy n-normed linear space,intuitionistic fuzzy n-norm,Best approximation
sets
http://ijfs.usb.ac.ir/article_346.html
http://ijfs.usb.ac.ir/article_346_6ab0231a438fcfe753f8e98b207a377c.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
09
METACOMPACTNESS IN L-TOPOLOGICAL SPACES
71
79
EN
Sunil
Jacob John
Department of Mathematics, National Institute of Technology
Calicut, Calicut-673601, Kerala, India
sunil@nitc.ac.in
T.
Baiju
Department of Mathematics, National Institute of Technology Calicut,
Calicut-673601, Kerala, India
bethelbai@yahoo.co.in
10.22111/ijfs.2008.348
In this paper the concept of metacompactness in L-topologicalspaces is introduced by means of point finite families of L-fuzzy sets. Thisfuzzy metacompactness is a natural generalization of Lowen fuzzy compactness.Further a characterization of fuzzy metacompactness in the weakly inducedL-topological spaces is also obtained.
L-topology,Fuzzy metacompactness
http://ijfs.usb.ac.ir/article_348.html
http://ijfs.usb.ac.ir/article_348_6213cfdd88862a790fbc012919f842d6.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
09
INTUITIONISTIC FUZZY QUASI-METRIC AND PSEUDO-METRIC SPACES
81
88
EN
Yongfa
Hong
College of Information Science and Engineering, Shandong University
of Science and Technology, Qingdao, Shandong, 266510, P. R. China
hzycfl@ 126.com
Xianwen
Fang
Department of Mathematics and Physics, Anhui University of Science
and Technology, Huainan,Anhui, 232001, P. R. China
Binguo
Wang
College of Information Science and Engineering, Shandong University
of Science and Technology, Qingdao, Shandong, 266510, P. R. China
10.22111/ijfs.2008.349
In this paper, we propose a new definition of intuitionistic fuzzyquasi-metric and pseudo-metric spaces based on intuitionistic fuzzy points. Weprove some properties of intuitionistic fuzzy quasi- metric and pseudo-metricspaces, and show that every intuitionistic fuzzy pseudo-metric space is intuitionisticfuzzy regular and intuitionistic fuzzy completely normal and henceintuitionistic fuzzy normal. These are the intuitionistic fuzzy generalization ofthe corresponding properties of fuzzy quasi-metric and pseudo- metric spaces.
Intuitionistic fuzzy quasi-metric spaces,Intuitionistic fuzzy pseudometric
spaces
http://ijfs.usb.ac.ir/article_349.html
http://ijfs.usb.ac.ir/article_349_e462bdee3462b5203d0b7af5bdba624c.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
09
THE DIRECT AND THE INVERSE LIMIT OF HYPERSTRUCTURES ASSOCIATED WITH FUZZY SETS OF TYPE 2
89
94
EN
Violeta Leoreanu
Fotea
Faculty of Mathematics, ”Al.I.Cuza” University, 6600 Iasi,
Romania
leoreanu2002@yahoo.com
10.22111/ijfs.2008.350
In this paper we study two important concepts, i.e. the direct andthe inverse limit of hyperstructures associated with fuzzy sets of type 2, andshow that the direct and the inverse limit of hyperstructures associated withfuzzy sets of type 2 are also hyperstructures associated with fuzzy sets of type 2.
Hyperstructure,Hypergroup,Fuzzy set of type 2,Direct limit,Inverse
limit
http://ijfs.usb.ac.ir/article_350.html
http://ijfs.usb.ac.ir/article_350_9c19173a4d46068588b174898d965fc8.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
5
3
2008
10
30
Persian-translation Vol.5, No.3, October 2008
97
104
EN
10.22111/ijfs.2008.2902
http://ijfs.usb.ac.ir/article_2902.html
http://ijfs.usb.ac.ir/article_2902_081e1c7c112e536df36567ef09aa9840.pdf