eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
259
267
10900
مقاله پژوهشی
G-frames in Hilbert Modules Over Pro-C*-algebras
N. Haddadzadeh
nhaddad25@gmail.com
1
Department of Mathematics, Abadan Branch, Islamic Azad University, Abadan, Iran.
G-frames are natural generalizations of frames which provide more choices on analyzing functions from frame expansion coefficients. First, they were defined in Hilbert spaces and then generalized on C*-Hilbert modules. In this paper, we first generalize the concept of g-frames to Hilbert modules over pro-C*-algebras. Then, we introduce the g-frame operators in such spaces and show that they share many useful properties with their corresponding notions in Hilbert spaces. We also show that, by having a g-frame and an invertible operator in this spaces, we can produce the corresponding dual g-frame. Finally we introduce the canonical dual g-frames and provide a reconstruction formula for the elements of such Hilbert modules.
http://ijim.srbiau.ac.ir/article_10900_a94f3ba0d977f2fe2236817e72d8490b.pdf
Pro-C*-algebra
Hilbert modules
G-frames
Frame operators
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
269
278
10901
مقاله پژوهشی
A New Group Data Envelopment Analysis Method for Ranking Design Requirements in Quality Function Deployment
J. Pourmahmoud
pourmahmoud@azaruniv.ac.ir
1
E. Babazadeh
2
Department of Applied Mathematics, Azarbaijan Shahid madani University, Tabriz, Iran.
Department of Applied Mathematics, Azarbaijan Shahid madani University, Tabriz, Iran.
Data envelopment analysis (DEA) is an objective method for priority determination of decision making units (DMUs) with the same multiple inputs and outputs. DEA is an efficiency estimation technique, but it can be used for solving many problems of management such as rankig of DMUs. Many researchers have found similarity between DEA and MCDM techniques. One of the earliest techniques in MCDM is Quality Function Deployment (QFD) which is a team-based and disciplined approach to product design, engineering and production and provides in-depth evaluation of a product. The QFD team is responsible for assessing the relationships between costumer requirements (CRs) and design requirements (DRs) and the interrelationships between DRs. In practice, each member demonstrates significantly different behavior from the others and generates different assessment results, leading to the QFD with uncertainty. In this paper data envelopment analysis is used to overcome this uncertainty. Each member's subjective assessment is taken into account directly and a new data envelopment analysis method in group situation is constructed which differs from multi-objective decision making models. Then, without using Charnes-Cooper transformation, the proposed model is transformed into a linear programing problem in a completely different manner. We will call the proposed model "Grouped-QFDEA".
http://ijim.srbiau.ac.ir/article_10901_0967a2dcd623f539dddbafdcb4732cae.pdf
Data envelopment analysis (DEA)
Quality function deployment (QFD)
Group situation
Multi-objective decision making models
Ranking
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
279
288
10906
مقاله پژوهشی
On Fuzzy Solution for Exact Second Order Fuzzy Differential Equation
A. Armand
1
Z. Gouyandeh
zgouyandeh@yahoo.com
2
Young Researchers and Elites Club, Yadegar-e-Imam Khomeini (RAH) Shahre Rey Branch, Islamic Azad University, Tehran, Iran.
Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran, Iran.
In the present paper, the analytical solution for an exact second order fuzzy initial value problem under generalized Hukuhara differentiability is obtained. First the solution of first order linear fuzzy differential equation under generalized Hukuhara differentiability is investigated using integration factor methods in two cases. The second based on the type of generalized Hukuhara differentiability, the analytical solution of an exact second order fuzzy initial value problem is derived in two senses of differentiability. Also, several properties for generalized Hukuhara differentiability are obtained on the topics, such as, the univariate fuzzy chain rules, fuzzy integration by parts, among others. At the end, some illustrative examples are presented and these examples show the behavior of the solutions.
http://ijim.srbiau.ac.ir/article_10906_d41d8cd98f00b204e9800998ecf8427e.pdf
Generalized Hukuhara differentiability
Switching point
Fuzzy first order differential equation
Second order exact fuzzy initial value problem
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
289
299
10922
مقاله پژوهشی
Effect of Hall Current and Wall Conductance on Hydromagnetic Natural Convective Flow Between Vertical Walls
D. Kumar
dileepyadav02april@gmail.com
1
A. K. Singh
2
Mr. Sarveshanand
3
Department of Mathematics, Institute of Science, Banaras Hindu University, Varanasi-221005, India.
Department of Mathematics, Institute of Science, Banaras Hindu University, Varanasi-221005, India.
Department of Mathematics, K. N. Govt. P. G. College, Gyanpur, Bhadohi- 221304, India.
This paper has examined the analytical solution of steady fully developed natural convective flow of a viscous incompressible and electrically conducting fluid between vertical channel by taking the Hall current and induced magnetic field into account. We have obtained the non-dimensional simultaneous ordinary differential equations using the suitable non-dimensional variables and parameters in the governing equations of the model. By obtaining the analytical solution of the simultaneous ordinary differential equations, the effects of the Hall current and the Hartmann number on the primary and secondary components of the velocity, induced magnetic field and induced current density are presented by the graphs. The influence of the Hall current is to increase both the primary and secondary components of the velocity and induced magnetic field profiles but decrease the components of induced current density. It is found that the effect of Hartmann number is to decrease both the primary and secondary components of velocity and induced current density but increase the components of the induced magnetic field.
http://ijim.srbiau.ac.ir/article_10922_8acb3372e1c03a262f5b975729318315.pdf
Hall current
Induced magnetic field
Natural convection
Hydromagnetic
Induced current density
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
301
306
10958
مقاله پژوهشی
Solving Volterra's Population Model via Rational Christov Functions Collocation Method
K. Parand
k\_parand@sbu.ac.ir
1
E. Hajizadeh
2
A. Jahangiri
3
S. Khaleqi
4
Department of Computer Sciences, Faculty of Mathematical, Shahid Beheshti University, Tehran, Iran.
Department of Computer Sciences, Faculty of Mathematical, Shahid Beheshti University, Tehran, Iran.
Department of Computer Sciences, Salman Farsi University of Kazerun, Kazerun, Iran.
Department of Computer Sciences, Faculty of Mathematical, Shahid Beheshti University, Tehran, Iran.
The present study is an attempt to find a solution for Volterra's Population Model by utilizing Spectral methods based on Rational Christov functions. Volterra's model is a nonlinear integro-differential equation. First, the Volterra's Population Model is converted to a nonlinear ordinary differential equation (ODE), then researchers solve this equation (ODE). The accuracy of method is tested in terms of $RES$ error and compare the obtained results with some well-known results.The numerical results obtained show that the proposed method produces a convergent solution.
http://ijim.srbiau.ac.ir/article_10958_8d8da42cbeb82cd5b86bf7b90edc32f7.pdf
Volterra's Population Model
collocation method
Rational Christov Functions
Nonlinear ODE
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
307
318
10973
مقاله پژوهشی
Environmental Assessment and Congestion for DMUs With Undesirable Outputs
M. Khodadadi
m.khodadadi@iaurmia.ac.ir
1
H. Zare Haghighi
2
Department of Mathematics, Urmia Branch, Islamic Azad University, Urmia, Iran.
Department of Mathematics, Urmia Branch, Islamic Azad University, Urmia, Iran.
In recent years, the assessment of environmental performance has been received considerable attention by environmental policy indicators and decision makers. In this regard, this paper applies data envelopment analysis (DEA) as a management tool for evaluating the environmental performance of the firms and uses the extended bounded adjusted measure (extended BAM) for including undesirable outputs in the environmental assessment. On the other hand, congestion points to a situation where inputs are excessively used. The previous studies of congestion mainly considered the framework of desirable outputs, and undesirable outputs have been disregarded in the evaluation. To overcome these shortcomings, this paper introduces an alternative definition and approach to treat congestion in the simultaneous presence of desirable and undesirable outputs. Then, the presented method is applied on 31 administrative regions of China. As a result of this application, it is observed that seven industries are environmentally efficient and also do not show congestion. Four industries evidence congestion in one or both of their inputs. By reducing the amount of congestion in each input, these industries can increase their desirable output and decrease their undesirable outputs.
http://ijim.srbiau.ac.ir/article_10973_9afc657735c9dc1617a68018d96b1511.pdf
Data envelopment analysis
Environmental performance
Congestion
Undesirable output
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
319
332
11055
مقاله پژوهشی
Impact of Outliers in Data Envelopment Analysis
A. Gholam Abri
1
Department of Mathematics, Firoozkooh Branch, Islamic Azad University, Firoozkooh, Iran.
This paper will examine the relationship between "Data Envelopment Analysis" and a statistical concept ``Outlier". Data envelopment analysis (DEA) is a method for estimating the relative efficiency of decision making units (DMUs) having similar tasks in a production system by multiple inputs to produce multiple outputs. An important issue in statistics is to identify the outliers. In this paper, we attempt to investigate the concept of the outliers determination by data envelopment analysis and assess the manner of decision making units when a sample contains an outlier. We will start by providing a review literature. We will then proceed with our proposed method and discuss the strengths and weaknesses of our method. We will provide some numerical results to demonstrate the applicability of our method.
http://ijim.srbiau.ac.ir/article_11055_15f195010890cc2bae410a2449e25f8d.pdf
Data envelopment analysis (DEA)
Statistics
Outlier
Efficiency
Normal Distribution
Production Possibility Set (PPS)
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
333
339
11636
مقاله پژوهشی
Another Method for Defuzzification Based On Characterization of Fuzzy Numbers
Rahim Saneifard
srsaneeifard@yahoo.com
1
Department of Mathematics, Urmia Branch, Urmia, Iran
Here we consider approaches to the ranking of fuzzy numbers based upon the idea of associating with a fuzzy number a scalar value, its signal/noise ratios, where the signal and the noise are defined as the middle-point and the spread of each $gamma$-cut of a fuzzy number, respectively. We use the value of a as the weight of the signal/noise ratio of each $gamma$-cut of a fuzzy number to calculate the ranking index of each fuzzy number. The proposed method can rank any kinds of fuzzy numbers with different kinds of membership functions.
http://ijim.srbiau.ac.ir/article_11636_759c59e16ecd7774a3e23ebd772a072d.pdf
Ranking
Fuzzy number
Defuzzification
Signal/noise ratios
eng
Science and Research Branch, Islamic Azad University, Tehran, Iran
International Journal of Industrial Mathematics
2008-5621
2008-563X
2017-09-01
9
4
341
347
11671
مقاله پژوهشی
Comparison Between Different Methods of Feature Extraction in BCI Systems Based on SSVEP
S. Sheykhivand
1
T. Yousefi Rezaii
2
A. Naderi Saatlo
3
N. Romooz
4
Department of Electrical and Computer Engineering University of Tabriz, Tabriz, Iran.
Department of Electrical and Computer Engineering University of Tabriz, Tabriz, Iran.
Department of Electrical-Electronics Engineering Urmia Branch, Islamic Azad University, Urmia, Iran.
Department of Electrical-Electronics Engineering Urmia Branch, Islamic Azad University, Urmia, Iran.
There are different feature extraction methods in brain-computer interfaces (BCI) based on Steady-State Visually Evoked Potentials (SSVEP) systems. This paper presents a comparison of five methods for stimulation frequency detection in SSVEP-based BCI systems. The techniques are based on Power Spectrum Density Analysis (PSDA), Fast Fourier Transform (FFT), Hilbert- Huang Transform (HHT), Cross Correlation and Canonical Correlation Analysis (CCA). The results demonstrate that the CCA and FFT can be successfully applied for stimulus frequency detection by considering the highest accuracy and minimum consuming time.
http://ijim.srbiau.ac.ir/article_11671_aba1d52169c3657d95e93a37415f3929.pdf
BCI
CCA
Cross Correlation
FFT
Fuzzy
HHT
PSDA
SSVEP