University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
30
Cover vol. 11, no. 4, August 2014
0
EN
10.22111/ijfs.2014.2685
http://ijfs.usb.ac.ir/article_2685.html
http://ijfs.usb.ac.ir/article_2685_df3214bfd0e8e4edcfffc5530c0163ea.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
30
Robust stability of stochastic fuzzy impulsive recurrent neural networks with\ time-varying delays
1
13
EN
M.
Syed Ali
Department of Mathematics, Thiruvalluvar University, Vellore - 632
106, Tamilnadu, India
syedgru@gmail.com
10.22111/ijfs.2014.1620
In this paper, global robust stability of stochastic impulsive recurrent neural networks with time-varyingdelays which are represented by the Takagi-Sugeno (T-S) fuzzy models is considered. A novel Linear Matrix Inequality (LMI)-based stability criterion is obtained by using Lyapunov functional theory to guarantee the asymptotic stability of uncertain fuzzy stochastic impulsive recurrent neural networks with time-varyingdelays. The results are related to the size of delay and impulses.Finally, numerical examples and simulations are given to demonstrate the correctness of the theoretical results.
Global asymptotic stability,Impulsive perturbations,Stochastic fuzzy recurrent neural networks,Time-varying delays
http://ijfs.usb.ac.ir/article_1620.html
http://ijfs.usb.ac.ir/article_1620_41dafc9887d401c5a0000ccd84aea553.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
30
Some conditions under which slow oscillation of a sequence of fuzzy numbers follows from Ces`{a}ro summability of its generator sequence
15
22
EN
Ibrahim
Canak
Department of Mathematics, Ege University, 35100, Izmir, Turkey
ibrahim.canak@ege.edu.tr
10.22111/ijfs.2014.1621
Let $(u_n)$ be a sequence of fuzzy numbers. We recover the slow oscillation of $(u_n)$ of fuzzy numbers from the Ces`{a}ro summability of its generator sequence and some additional conditions imposed on $(u_n)$. Further, fuzzy analogues of some well known classical Tauberian theorems for Ces`{a}ro summability method are established as particular cases.
Ces\`{a}ro summability,Slow oscillation,Tauberian theorems,Sequences of fuzzy numbers
http://ijfs.usb.ac.ir/article_1621.html
http://ijfs.usb.ac.ir/article_1621_c2384221ff3393272720aaa1f664d782.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
30
A duality between fuzzy domains and strongly completely distributive $L$-ordered sets
23
43
EN
W.
Yao
Department of Mathematics, Hebei University of Science and Technology,
Shijiazhuang 050018, P.R. China
yaowei0516@163.com
B.
Zhao
Department of Mathematics, Shaanxi Normal University, Xi'an 710062,
P.R. China
zhaobin@snnu.edu.cn
10.22111/ijfs.2014.1622
The aim of this paper is to establish a fuzzy version of the dualitybetween domains and completely distributive lattices. All values aretaken in a fixed frame $L$. A definition of (strongly) completelydistributive $L$-ordered sets is introduced. The main result inthis paper is that the category of fuzzy domains is dually equivalentto the category of strongly completely distributive $L$-orderedsets. The results in this paper establish close connections amongfuzzy-set approach of quantitative domains and fuzzy topology withmodified $L$-sober spaces and spatial $L$-frames as links. Inaddition, some mistakes in [K.R. Wagner, Liminf convergence in$Omega$-categories, Theoretical Computer Science 184 (1997)61--104] are pointed out.
Fuzzy DCPO,Fuzzy domain,Fuzzy Scott
topology,(Spatial) $L$-frame,$L$-frame homomorphism,(Strongly)
Completely distributive $L$-ordered set,Modified $L$-sober
http://ijfs.usb.ac.ir/article_1622.html
http://ijfs.usb.ac.ir/article_1622_dad91c3aea817c8872a7af7d2eb80c03.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
30
Convergence of a semi-analytical method on the fuzzy linear systems
45
60
EN
Mojtaba
Ghanbari
Department of Mathematics, Aliabad Katoul Branch, Islamic
Azad University, Aliabad Katoul, Iran
mojtaba.ghanbari@gmail.com
Rahele
Nuraei
Department of Mathematics, South Tehran Branch, Islamic Azad
University, Tehran, Iran
rahele.nuraei@gmail.com
10.22111/ijfs.2014.1623
In this paper, we apply the homotopy analysis method (HAM) for solving fuzzy linear systems and present the necessary and sufficient conditions for the convergence of series solution obtained via the HAM. Also, we present a new criterion for choosing a proper value of convergence-control parameter $hbar$ when the HAM is applied to linear system of equations. Comparisons are made between the results of the HAM and several well-known numerical algorithms such as Jacobi method (JM), Gauss-Seidel method (GSM), successive over relaxation method (SOR), Adomian decomposition method (ADM) and homotopy perturbation method (HPM).
Fuzzy linear system,Homotopy analysis method,Convergence-control parameter,Numerical algorithms
http://ijfs.usb.ac.ir/article_1623.html
http://ijfs.usb.ac.ir/article_1623_7d9b0b310e31e8b8041af9982d4fdddf.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
30
Fuzzy Acts over Fuzzy Semigroups and Sheaves
61
73
EN
M.
Haddadi
Department of Mathematics, Statistics and Computer Sciences, Semnan
University, Semnan, Iran
m.haddadi@semnan.ac.ir
10.22111/ijfs.2014.1624
lthough fuzzy set theory and sheaf theory have been developed and studied independently, Ulrich Hohle shows that a large part of fuzzy set theory is in fact a subfield of sheaf theory. Many authors have studied mathematical structures, in particular, algebraic structures, in both categories of these generalized (multi)sets. Using Hohle's idea, we show that for a (universal) algebra $A$, the set of fuzzy algebras over $A$ and the set of subalgebras of the constant sheaf of algebras over $A$ are order isomorphic. Then, among other things, we study the category of fuzzy acts over a fuzzy semigroup, so to say, with its universal algebraic as well as classic algebraic definitions.
fuzzy algebra,fuzzy act,sheaf
http://ijfs.usb.ac.ir/article_1624.html
http://ijfs.usb.ac.ir/article_1624_7915f082437e766d5e60d3f04c95a162.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
30
A note on convergence in fuzzy metric spaces
75
85
EN
Valentn
Gregori
Instituto Universitario de Matematica Pura y Aplicada, Universitat
Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain
vgregori@mat.upv.es
Juan-Jose
Minana
Instituto Universitario de Matematica Pura y Aplicada, Universitat
Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain
jj.minana@uib.es
Samuel
Morillas
Instituto Universitario de Matematica Pura y Aplicada, Universitat
Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain
smorillas@mat.upv.es
10.22111/ijfs.2014.1625
The sequential $p$-convergence in a fuzzy metric space, in the sense of George and Veeramani, was introduced by D. Mihet as a weaker concept than convergence. Here we introduce a stronger concept called $s$-convergence, and we characterize those fuzzy metric spaces in which convergent sequences are $s$-convergent. In such a case $M$ is called an $s$-fuzzy metric. If $(N_M,ast)$ is a fuzzy metric on $X$ where $N_M(x,y)=bigwedge{M(x,y,t):t>0}$ then it is proved that the topologies deduced from $M$ and $N_M$ coincide if and only if $M$ is an $s$-fuzzy metric.
Fuzzy metric space,principal fuzzy metric,$p$-convergence
http://ijfs.usb.ac.ir/article_1625.html
http://ijfs.usb.ac.ir/article_1625_4434683a72324a1c1ff35fc7fe0b6565.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
30
H"{o}lder summability method of fuzzy numbers and a Tauberian theorem
87
93
EN
Ibrahim
Canak
Department of Mathematics, Ege University, 35100, Izmir, Turkey
ibrahim.canak@ege.edu.tr
10.22111/ijfs.2014.1626
In this paper we establish a Tauberian condition under which convergence follows from H"{o}lder summability of sequences of fuzzy numbers.
H\"{o}lder means,Slow
oscillation,Tauberian theorems,Fuzzy numbers
http://ijfs.usb.ac.ir/article_1626.html
http://ijfs.usb.ac.ir/article_1626_6d6b326e6429a049c79be13e505260bb.pdf
University of Sistan and Baluchestan
Iranian Journal of Fuzzy Systems
1735-0654
11
4
2014
08
01
Persian-translation vol. 11, no. 4, August 2014
97
103
EN
10.22111/ijfs.2014.2686
http://ijfs.usb.ac.ir/article_2686.html
http://ijfs.usb.ac.ir/article_2686_9fb11a1425907d3407c92ae6a853c5b2.pdf