eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
331
337
9533
مقاله پژوهشی
Extensions of Regular Rings
SH. A. Safari Sabet
1
M. Farmani
mino.farmani@gmail.com
2
Department of Mathematics, Central Tehran Branch, Islamic Azad University, Tehran, Iran
Young Researchers and Elite Club, Roudehen Branch, Islamic Azad University, Roudehen, Iran
Let $R$ be an associative ring with identity. An element $x in R$ is called $mathbb{Z}G$-regular (resp. strongly $mathbb{Z}G$-regular) if there exist $g in G$, $n in mathbb{Z}$ and $r in R$ such that $x^{ng}=x^{ng}rx^{ng}$ (resp. $x^{ng}=x^{(n+1)g}$). A ring $R$ is called $mathbb{Z}G$-regular (resp. strongly $mathbb{Z}G$-regular) if every element of $R$ is $mathbb{Z}G$-regular (resp. strongly $mathbb{Z}G$-regular). In this paper, we characterize $mathbb{Z}G$-regular (resp. strongly $mathbb{Z}G$-regular) rings. Furthermore, this paper includes a brief discussion of $mathbb{Z}G$-regularity in group rings.
http://ijim.srbiau.ac.ir/article_9533_aad09288e1c7ae1bcb5bf9a713da1909.pdf
Group ring
$pi$-Regular
$mathbb{Z}G$-Regular
Strongly $mathbb{Z}G$-regular
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
339
346
9551
مقاله پژوهشی
Computational technique of linear partial differential equations by reduced differential transform method
H. Rouhparvar
rouhparvar59@gmail.com
1
Department of Mathematics, College of Technical and Engineering, Saveh Branch, Islamic Azad University, Saveh, Iran
This paper presents a class of theoretical and iterative method for linear partial differential equations. An algorithm and analytical solution with a initial condition is obtained using the reduced differential transform method. In this technique, the solution is calculated in the form of a series with easily computable components. There test modeling problems from mathematical mechanic, physic, electronic and so on, and are discussed to illustrate the effectiveness and the performance of the our method.
http://ijim.srbiau.ac.ir/article_9551_a54070a19a7e57fc824df2d191b34f1b.pdf
Reduced differential transform method
Taylor series
Parabolic equations
Hyperbolic equations
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
347
363
9555
مقاله پژوهشی
Effect of slip and variable thermal boundary conditions on hydromagnetic mixed convection flow and heat transfer from a non-linearly stretching surface
M. Abd El-Aziz
$m_{-}$abdelaziz999@yahoo.com
1
King Khaled University, Faculty of Science, Mathematics Department, Abha 9004, Saudi Arabia.|Department of Mathematics, Faculty of Science, Helwan University, Cairo, Egypt P. O. Box 11795.
The effect of partial slip and temperature dependent fluid properties on the MHD mixed convection flow from a heated, non-linearly stretching surface in the presence of radiation and non-uniform internal heat generation/absorption is investigated. The velocity of the stretching surface was assumed to vary according to power-law form. Thermal transport is analyzed for two types of non-isothermal boundary conditions, variable wall temperature (VWT) and variable surface heat flux (VHF) of the power-law form. The analysis accounts for both temperature dependent viscosity and temperature dependent thermal conductivity. The governing differential equations are transformed by introducing proper non-similarity variables and are solved numerically. The physical significance of the slip parameter, magnetic parameter, radiation parameter, viscosity-temperature parameter, thermal conductivity parameter and buoyancy force parameter on the flow and the thermal fields are shown through graphs and discussed in detail. The values of wall shear stress and the local Nusselt number are tabulated.
http://ijim.srbiau.ac.ir/article_9555_a2a27958bb22d0852ec7e266557a58a6.pdf
Slip flow
Mixed convection
Heat source
Stretching surface
Magnetic field
Radiation
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
365
375
9556
مقاله پژوهشی
A new attitude coupled with the basic thinking to ordering for ranking fuzzy numbers
F. Abbasi
k.9121946081@gmail.com
1
T. Allahviranloo
2
S. Abbasbandy
3
Department of Mathematics, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran.
Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Ranking fuzzy numbers is generalization of the concepts of order, and class, and so have fundamental applications. Moreover, deriving the final efficiency and powerful ranking are helpful to decision makers when solving fuzzy problems. Selecting a good ranking method can apply to choosing a desired criterion in a fuzzy environment. There are numerous methods proposed for the ranking of fuzzy numbers, some of them seem to be good in a particular context but not in general. In this paper, a new attitude coupled with the basic thinking of ordering for ranking of fuzzy numbers is proposed. The properties of the proposed method are discussed in detail. The ranking results show that the proposed method can overcome certain shortcomings that exist in the previous ranking methods.The method also has very easy and simple calculations compared to other methods. Finally, numerical examples are presented to illustrate the advantage of our proposed method, and compare them with other common ranking methods. The future prospect of this paper is a new attitude to fuzzy distance, which will be referred to in the end.
http://ijim.srbiau.ac.ir/article_9556_3acd646ceff799f65c877cee6ecb9359.pdf
Ranking fuzzy numbers
Transmission average (TA)
Fuzzy par
Ambiguity rank
Fuzzy partial order
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
377
384
9557
مقاله پژوهشی
Ashwini Index of a Graph
Sunilkumar M. Hosamani
sunilkumar.rcu@gmail.com
1
Department of Mathematics, Rani Channamma University, Belagavi, India.
Motivated by the terminal Wiener index, we define the Ashwini index $mathcal{A}$ of trees as begin{eqnarray*} % nonumber to remove numbering (before each equation)
mathcal{A}(T) &=& sumlimits_{1leq i
http://ijim.srbiau.ac.ir/article_9557_643f841facfbd226e1e6257ba6057b2f.pdf
Wiener index
terminal Wiener index, Ashwini index
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
385
394
9561
مقاله پژوهشی
A new evaluation model for selecting a qualified manager by using fuzzy Topsis approach
S. M. Hosseini
seimehhos@yahoo.com
1
Department of Manegment, Firoozkooh Branch, Islamic Azad University, Firoozkooh, Iran.
Considering the contemporary business settings, managers’ role is more than essential to the viability and further development of an organization. Managers should possess such skills in order to effectively cope with the competition. Multiple attributes decision making (MADM) is an approach employed to solve problems involving selection from among a finite number of alternatives. The aim of this study is to develop a methodology to evaluate managers based on integrating fuzzy AHP and fuzzy TOPSIS approaches. In this paper, I have taken into consideration some important criteria which affect the process of managers selection. I have calculated the weights for each criterion based on Interval-valued fuzzy AHP and then inputted these weights to the fuzzy TOPSIS method to rank managers. The entire methodology is illustrated with the help of a numerical example and finally the rank of each managers is determined according to its results. The proposed method enables decision analysts to better understand the complete evaluation process and provide a more accurate, effective, and systematic decision support tool. Also, the proposed method provides a useful
way for handling fuzzy TOPSIS based on fuzzy numbers.
http://ijim.srbiau.ac.ir/article_9561_f6c92e7e8329ead8edafa58dc6fe21d6.pdf
Fuzzy number
Fuzzy TOPSIS
Multiple criteria decision-making
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
395
400
9562
مقاله پژوهشی
The Solution of Fully Fuzzy Quadratic Equations Based on Restricted Variation
L. Gerami Moazam
lgerami.moazam@yahoo.com
1
Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Firstly, in this paper, we apply the Fuzzy Restricted Variation Method to achieve an analytical and approximate unsymmetrical fuzzy solution for Fully Fuzzy Quadratic Equation. In this application, after finding the real root of 1-cut of $tilde{A}tilde{X}^{2}+tilde{B}tilde{X}+tilde{C}=tilde{D}$, initial guess is always chosen with possible unknown parameters that leads to highly accurate solution. This technique is applying to solve mentioned equation in four cases via the sign of coefficients and variable that there is not zero in support of them and we solve the problems to find positive or negative solution. This method has been shown to solve effectively, easily and accurately a large class of nonlinear quadratic equations with approximations converging rapidly to accurate solution. In this paper we present the solutions in four cases with formulas, that can be used to write the algorithm for this technique. Finally to illustrate easy application and rich behavior of this method, several examples are given.
http://ijim.srbiau.ac.ir/article_9562_011cdf8865ceb58346b1818517838614.pdf
Fuzzy number
Fully fuzzy quadratic equation
Fuzzy parametric form
Restricted variations
Unsymmetrical fuzzy solution
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
401
414
9594
مقاله پژوهشی
Unsteady MHD Couette-Hartmann flow through a porous medium bounded by porous plates with Hall current, ion-slip and Coriolis effects
J. K. Singh
s.jitendrak@yahoomail.com
1
S. Ghousia Begum
2
N. Joshi
3
Department of Mathematics, V. S. K. University, Bellary-583105, INDIA.
Department of Mathematics, V. S. K. University, Bellary-583105, INDIA.
Department of Mathematics, V. S. K. University, Bellary-583105, INDIA.
Effects of Hall current, ion-slip and Coriolis force on unsteady MHD Couette-Hartmann flow of a viscous incompressible electrically conducting fluid through a porous medium bounded by porous plates in the presence of a uniform transverse magnetic field which is either fixed relative to the fluid or to the moving porous plate is investigated using Laplace transform technique. The expressions for the fluid velocity and shear stress at the moving porous plate are also derived. In order to analyze the physical significance and characteristic features of the problem, the graphs for velocity distribution and shear stress distribution at the moving porous plate are generated for different values of non-dimensional parameters. It is observed that the fluid velocity when magnetic field is fixed relative to the moving porous plate is always more than the fluid velocity when magnetic field is fixed relative to the fluid while the shear stress at the moving porous plate when magnetic field is fixed relative to the moving porous plate is always less than the shear stress at the moving porous plate when magnetic field is fixed relative to the fluid.
http://ijim.srbiau.ac.ir/article_9594_0eb522d2361240526e9dd65510f41fd8.pdf
Magnetic field
Hall current
Ion-slip
Coriolis force
Permeability and suction/injection
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
415
421
9595
مقاله پژوهشی
Modified homotopy perturbation method for solving non-linear oscillator's equations
A. R. Vahidi
alrevahidi@yahoo.com
1
Z. Azimzadeh
2
M. Shahrestani
3
Department of Mathematics, College of Science,Yadegar-e-Imam Khomeini (RAH) Shahr-e-Rey Branch, Islamic Azad University, Tehran, Iran.
Department of Mathematics, College of Science,Yadegar-e-Imam Khomeini (RAH) Shahr-e-Rey Branch, Islamic Azad University, Tehran, Iran.
Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran, Iran.
In this paper a new form of the homptopy perturbation method is used for solving oscillator differential equation, which yields the Maclaurin series of the exact solution. Nonlinear vibration problems and differential equation oscillations have crucial importance in all areas of science and engineering. These equations equip a significant mathematical model for dynamical systems. The accuracy of the Solution equation is very important because the analysis component of the system like vibration amplitude control, synchronization dynamics are dependent to the exact solution of oscillation equation.
http://ijim.srbiau.ac.ir/article_9595_36b2ce580c4336cd683a0d42c6a14e61.pdf
Homotopy perturbation method (HPM)
Differential equations
Non-linear oscillator's equation
Laplace transformation
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
423
430
9617
مقاله پژوهشی
Approximation solution of two-dimensional linear stochastic Volterra-Fredholm integral equation via two-dimensional Block-pulse functions
M. Fallahpour
1
M. Khodabin
m-khodabin@kiau.ac.ir
2
K. Maleknejad
3
Department of Mathematics, Karaj Branch, Islamic Azad University, Karaj, Iran.
Department of Mathematics, Karaj Branch, Islamic Azad University, Karaj, Iran.
Department of Mathematics, Karaj Branch, Islamic Azad University, Karaj, Iran.
In this paper, a numerical efficient method based on two-dimensional block-pulse functions (BPFs) is proposed to approximate a solution of the two-dimensional linear stochastic Volterra-Fredholm integral equation. Finally the accuracy of this method will be shown by an example.
http://ijim.srbiau.ac.ir/article_9617_744373b68d9d7d266f0597aa488ec6fc.pdf
Block-pulse function
Two-dimensional equation
Stochastic integral equation
Volterra-fredholm integral
operational matrix
Brownian motion process
Ito integral
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2016-11-01
8
4
431
435
10179
Another Method for Defuzzification Based on Regular Weighted Point
Rasoul Saneifard
1
Rahim Saneifard
srsaneeifard@yahoo.com
2
Department of Engineering Technology, Texas Southern University, Houston, Texas, USA.
Department of Applied Mathematics, Urmia Branch, Islamic Azad University, Urmia, Iran.
A new method for the defuzzification of fuzzy numbers is developed in this paper. It is well-known, defuzzification methods allow us to find aggregative crisp numbers or crisp set for fuzzy numbers. But different fuzzy numbers are often converted into one crisp number. In this case the loss of essential information is possible. It may result in inadequate final conclusions, for example, expert estimation problems, prediction problems, etc. Accordingly, the necessity to develop a method for the defuzzification of fuzzy numbers, allowing us to save their informative properties has arisen. The purpose of this paper is to develop such a method. The method allows us to find aggregative intervals for fuzzy numbers. These intervals are called the Regular weighted intervals. We start with the definition of regular weighted points for fuzzy numbers. The regular weighted interval for fuzzy number is defined as the set of regular weighted points of all unimodal numbers, that belong to this number. Some propositions and examples about regular weighted point and regular weighted intervals properties are offered.
http://ijim.srbiau.ac.ir/article_10179_20c059175ef920233f99fae0acbef646.pdf
Ranking
Fuzzy number
L-R type
Defuzzification
Regular weighted point