Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
6
3
2014
05
01
Evaluation and ranking of suppliers with fuzzy DEA and PROMETHEE approach
189
197
EN
R.
Radfar
Department of Industrial Management, Science and Research Branch, Islamic Azad University, Tehran, Iran
r.radfar@srbiau.ac.ir
F.
Salahi
Department of Industrial Management, Science and Research Branch, Islamic Azad University, Tehran, Iran
Supplier selection is a multi-Criteria problem. This study proposes a hybrid model for supporting the suppliers’ selection and ranking. This research is a two-stage model designed to fully rank the suppliers where each supplier has multiple Inputs and Outputs. First, the supplier evaluation problem is formulated by Data Envelopment Analysis (DEA), since the regarded decision deals with uncertainly and ambiguity of data as well as experts and manager linguistic judgment the proposed model is equipped with Fuzzy approach, then in this research we use of Fuzzy DEA for first stage. In the second stage, efficient suppliers are ranked with Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) model. Fuzzy DEA PROMETHEE ranking does not replace the DEA classification model; rather it furthers the analysis by providing full ranking in DEA context for efficient suppliers.
supplier selection,Data Envelopment Analysis,Fuzzy,Efficient,multi-criteria,Preference Ranking Organization Method for Enrichment Evaluation
http://ijim.srbiau.ac.ir/article_2546.html
http://ijim.srbiau.ac.ir/article_2546_707a8bbbd49d8a68b815e57739477372.pdf
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
6
3
2014
05
01
Magnetic fluid lubrication of porous pivoted slider bearing with slip and squeeze velocity
199
206
EN
Rajesh C.
Shah
Department of Applied Mathematics, Faculty of Technology and Engineering,
The M. S. University of Baroda, Vadodara 390 001, Gujarat State, India.
dr_rcshah@yahoo.com
Dilip B.
Patel
Department of Mathematics,
Sankalchand Patel College of Engineering, Visnagar 384 315, Gujarat State, India.
In this paper the problem on “Magnetic fluid lubrication of porous-pivoted slider bearing with slip velocity by N Ahmad et.al.[7]” has been recapitulated using Jenkin’s model [4] with the additional effect of squeeze velocity of the above plate. It is found that while discussing the above problem, [7] has stated but ignored the term , where +, in their study (Refer equation(2.2)). This paper reconsiders the above neglected term with , where . Since is the corotational derivative of magnetization vector, so it has an impact on the performance of the problem [9]. With the addition of the above term and under an oblique magnetic field, it is found that the dimensionless load carrying capacity can be improved substantially with and without squeeze effect. The paper also studied in detail about the effects of squeeze velocity and sliding velocity. It is observed that dimensionless load carrying capacity increases when squeeze velocity increases and sliding velocity decreases.
Magnetic fluid,Slider bearing,Slip velocity,Squeeze velocity,Jenkin’s model
http://ijim.srbiau.ac.ir/article_2547.html
http://ijim.srbiau.ac.ir/article_2547_a4097efb6dfd2cad69af16939cfc1ec3.pdf
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
6
3
2014
05
01
Variational iteration method for solving nth-order fuzzy integro-differential equations
207
214
EN
O.
Sedaghatfar
Department of Mathematics, Shahr-e-rey Branch, Islamic Azad University, Shahr-e-Rey, Iran.
sedaghatfar@yahoo.com
S.
Moloudzadeh
Department of Mathematics, Faculty of Science, University of Duhok, Kurdistan Region, Duhok, Iraq
P.
Darabi
Department of Mathematics, Borujerd Branch, Islamic Azad University, Borujerd, Iran
In this paper, the variational iteration method for solving nth-order fuzzy integro differential equations (nth-FIDE) is proposed. In fact the problem is changed to the system of ordinary fuzzy integro-differential equations and then fuzzy solution of nth-FIDE is obtained. Some examples show the efficiency of the proposed method.
Variational iteration method,nth-order fuzzy integro-differential equations (nth-FIDE),The system of ordinary fuzzy integro-differential equations
http://ijim.srbiau.ac.ir/article_2620.html
http://ijim.srbiau.ac.ir/article_2620_9f2d84f511e3c4f0d0952631927d9821.pdf
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
6
3
2014
05
01
A multi-product vehicle routing scheduling model with time window constraints for cross docking system under uncertainty: A fuzzy possibilistic-stochastic programming
215
228
EN
B.
Vahdani
Young Researchers and Elite Club, Qazvin Branch, Islamic Azad University, Qazvin, Iran
b.vahdani@gmail.com
SH.
Sadigh Behzadi
Department of Mathematics, Islamic Azad University, Qazvin Branch, Qazvin, Iran
Mathematical modeling of supply chain operations has proven to be one of the most complex tasks in the field of operations management and operations research. Despite the abundance of several modeling proposals in the literature; for vast majority of them, no effective universal application is conceived. This issue renders the proposed mathematical models inapplicable due largely to the fact that real-life supply chain problems are set forth in restrained terms or represented less strikingly than they would bear out. This paper is triggered to bridge this gap by proposing a universal mixed integer linear programming (MILP) framework which to large extent simulates many realistic considerations in vehicle routing scheduling problems in cross-docking systems which might have separately been attempted by other researchers. The developed model is pioneer in excogitating the vehicle routing scheduling problem with the following assumptions: a) multiple products are transported between pick-up and delivery nodes, b) delivery time-intervals are imposed on each delivery node, c) multiple types of vehicles operate in the system, d) capacity constraints exists for each vehicle type, and finally e) vehicles arrives simultaneously at cross-docking location. Moreover, to solve the model a hybrid solution methodology is presented by combining fuzzy possibilistic programming and stochastic programming. Finally, in order to demonstrate the accuracy and efficiency of the proposed model, an extensive sensitivity analysis is performed to scrutinize its parameters’ demeanors.
Cross docking,Vehicle routing scheduling,Fuzzy possibilistic programming,stochastic programming
http://ijim.srbiau.ac.ir/article_2522.html
http://ijim.srbiau.ac.ir/article_2522_341f5ac5e5f23dd6408619a6dbe6a5e8.pdf
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
6
3
2014
05
01
The embedding method to obtain the solution of fuzzy linear systems
229
233
EN
T.
Allahviranloo
Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran, Iran.
allahviranloo@yahoo.com
A.
Hashemi
Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran, Iran.
In this paper, we investigate the general fuzzy linear system of equations. The main aim of this paper is based on the embedding approach. We ﬁnd the necessary and sufﬁcient conditions for the existence of fuzzy solution of the mentioned systems. Finally, Numerical examples are presented to more illustration of the proposed model.
Fuzzy linear system,Embedding method,Fuzzy numbers
http://ijim.srbiau.ac.ir/article_2200.html
http://ijim.srbiau.ac.ir/article_2200_e7e24ca27ec0917ff692d41493cdc752.pdf
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
6
3
2014
05
01
The Ritz-Galerkin method for MHD Couette flow of non-Newtonian fluid
235
243
EN
Z.
Barikbin
Department of Mathematics, Imam Khomeini International University, Ghazvin, 34149, Iran
monabarikbin@gmail.com
R.
Ellahi
Department of Mathematics & Statistics, Faculty of Basic and Applied Sciences,
International Islamic University, Islamabad, Pakistan
S.
Abbasbandy
Department of Mathematics, Imam Khomeini International University, Ghazvin, 34149, Iran
abbasbandy@yahoo.com
In this paper, the Ritz-Galerkin method in Bernstein polynomial basis is applied for solving the nonlinear problem of the magnetohydrodynamic (MHD) flow of third grade fluid between the two plates. The properties of the Bernstein polynomials together with the Ritz-Galerkin method are used to reduce the solution of the MHD Couette flow of non-Newtonian fluid in a porous medium to the solution of algebraic equations.
Ritz-Galerkin method,Bernstein polynomials,Satisfier function,MHD
http://ijim.srbiau.ac.ir/article_2548.html
http://ijim.srbiau.ac.ir/article_2548_4edf3361e482491a3224b917728bf7cd.pdf
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
6
3
2014
05
01
An improved approach for ranking the candidates in a voting system based on efficiency intervals
245
254
EN
A. A.
Foroughi
Department of Mathematics, University of Qom, Isfahan old road, Qom, 3716146611, Iran.
a-foroughi@qom.ac.ir
This paper proposes improvements and revisions to a recent approach in a voting system, and provides an effective approach with a stronger discriminate power. For this purpose, the advantage of a linear transformation is utilized to redene a previously used concept of virtual worst candidate, by incorporating the existing weight restrictions. Then, the best score of this virtual candidate is used as a lower bound for the scores of the candidates in the models. It is shown that the proposed approach overcomes some drawbacks in the existing models. The approach determines interval eciencies which can be used in ranking the candidates. Numerical examples illustrate some advantages of the proposed approach.
Data Envelopment Analysis,Voting,Ranking,Interval efficiency,The least relative total
score
http://ijim.srbiau.ac.ir/article_2800.html
http://ijim.srbiau.ac.ir/article_2800_b56e20e73e21bab284dd11d72d416f3a.pdf
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
6
3
2014
05
01
The study of the effective factors on investment in private sector in Iran “With emphasis on uncertainty”
255
264
EN
Z.
Rozeei
Department of Economics, Islamic Azad University, West Azerbaijan, Science and Research Branch, Iran
T.
Akhondzadeh
Department of Economics, Urmia Branch, Islamic Azad University, Orumieh Iran
tahereh.akhoondzadeh@gmail.com
G.
Sameei
Department of Economics, Urmia Branch, Islamic Azad University, Orumieh Iran
Making capital and investment is the main driving forces of economic development. Based on the investment sensitivity to the changes of some of macro-economic variables and risk and uncertainty, the present study evaluated the effective factors on investment in private sector in Iran during 1980-2007. At first, the uncertainty variables of real informal exchange rate, nominal interest rate and inflation rate were calculated by GARCH model. Then, by ARDL model, the effect of calculated uncertainty indices besides the main values of the variables and some of the other control variables on investment in private sector in Iran was investigated. The estimation results showed the negative uncertainty effect of the real exchange rate, inflation rate and nominal interest rate on investment in private sector in short-term and long-term. Also, the gross domestic production and inflation rate had significant and positive and negative effect, respectively on investment in private sector in Iran. In this model, there was no relationship between the size of civil expenditures of the government and real exchange rate with the private sector investment in our country. The error correction term coefficient showed that moderation to balance is done during more than 3 years.
Investment in private sector,Uncertainty of real exchange rate,Uncertainty of nominal interest rate,uncertainty of inflation rate,GARCH,ARDL
http://ijim.srbiau.ac.ir/article_2605.html
http://ijim.srbiau.ac.ir/article_2605_3c5734aee9ef07ad9e77a01eac482bb8.pdf