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Hadi-Vencheh A.,Islamic Azad University at Khorasgan | Hejazi S.,Islamic Azad University at Dehaghan | Eslaminasab Z.,Islamic Azad University at Khorasgan
Neural Computing and Applications | Year: 2013

In traditional approach, failure mode and effects analysis determines the risk priories of failure modes through the risk priority number which is determined by multiplication of three risk factors namely, failure occurrence (O), failure severity (S) and failure detection ability (D). In this approach, different weights of risk factors were not taken into consideration so that the three risk factors were assumed to have the same weight. This may not be realistic in real applications. In this paper we treat the risk factors as fuzzy variables and evaluate them using fuzzy linguistic terms and fuzzy ratings. As a result, fuzzy risk priority numbers (FRPNs) are proposed for prioritization of failure modes. The FRPNs are defined as fuzzy geometric means of the fuzzy ratings for O, S and D and can be computed using alpha-level sets and linear programming models. A numerical example is provided to examine the results of this model. © 2012 Springer-Verlag London Limited.


Haghighatian M.,Islamic Azad University at Dehaghan | Sanatkhah A.,Islamic Azad University at Kermān
Advances in Environmental Biology | Year: 2014

At present, since Iran is under several different kinds of boycott, reducing international economic dependence and promoting domestic production is of the utmost importance. Hence, in this study the relationship between the residents' in-group and out-group social capital and their support of domestic production in the city of Kerman is investigated. Research population consisted of all residents of Kerman who were 15 years old and above of which 400 individuals were selected through multi-stage cluster and quota sampling technique. The ideas of Putnam, Coleman, and Arrow provided the theoretical framework. Research results showed that bonding social capital (r=0.14) and bridging social capital (r=0.24) were positively and significantly related to residents' support of domestic. © 2014 AENSI Publisher All rights reserved.


Hadad M.,Islamic Azad University at Dehaghan | Sadeghi B.,Tarbiat Modares University
Journal of Cleaner Production | Year: 2013

A number of studies have shown that compared to dry machining; MQL technique substantially enhances cutting performance in terms of increasing tool life and improving the quality of the machined parts. But, there have been a few investigations about the influence of process parameters on the results, such as MQL nozzle position and cutting parameters (cutting speed, depth of cut and feed). The current study aims to show through experiment, the effects of the above parameters on turning performance such as machining forces, surface roughness and temperature. Furthermore, this paper presents a new method to calculate average temperatures and the heat partition to the tool, workpiece and chip during MQL turning. This model also can be used for other turning operations such as dry and conventional wet turning processes. In other words, to more accurately predict machining temperatures and heat fluxes, convection heat transfer coefficient of MQL/fluid in the rake and flank faces of the tool have been made to the thermal model. The tool-chip interface temperature of turning AISI 4140 steel in which the oil mist is supplied from both nozzles to the rake and flank faces is approximately 350 C lower than that in dry turning. If the oil mist is supplied only to rake face, the tool temperature is about 200 C lower than that in dry turning. Additionally, in wet turning, the tool-chip interface temperature is about 300 C lower than that in dry turning. © 2013 Elsevier Ltd. All rights reserved.


Shahreza A.R.,Islamic Azad University at Dehaghan | Imani H.,University of Kashan
Energy Conversion and Management | Year: 2015

A novel small scale model of solar chimney was investigated experimentally and numerically. Air flow, heat transfer and flow characteristics were numerically calculated and compared with the experimental results in this paper. Two intensifiers were used to intensify the heat flux radiated by the sun all around the solar chimney in the experimental case. An air tank was located downside the system to increase the absorption of the solar radiation reflected by the intensifiers. RNG k-ε model was chosen to simulate the turbulence and the well-known SIMPLE algorithm was used to solve the coupled velocity and pressure equations. Results show that utilization of intensifiers caused an increase in velocity magnitude in the chimney and consequently more power was generated. The maximum velocity of 5.12 m/s was reached which is remarkable, considering the small size of the SC structure. © 2014 Elsevier Ltd.


Hadad M.,Islamic Azad University at Dehaghan | Hadi M.,Islamic Azad University at Dehaghan
International Journal of Advanced Manufacturing Technology | Year: 2013

In grinding process, the abrasives plunge and slide against the workpiece during material removal with high specific energy consumption and high grinding zone temperature. To improve process efficiency, lubrication becomes an important requirement of the grinding fluids, along with chip removal and cooling the grinding zone. Grinding fluids have negative influences on the working environment and machining cost in terms of the health of the machine operator, pollution, the possibility of explosion (for oil), filtering, and waste disposal. The use of minimum quantity of lubrication (MQL) with an extremely low consumption of lubricant has been reported as a technologically and environmentally feasible alternative to flood cooling. This paper deals with an investigation of the grindability of hardened stainless steel (UNS S34700) and aluminum alloy AA6061 using dry, MQL, and conventional fluid techniques. One type of SiC and five types of Al2O3 wheels (corundum) as well as vegetable and synthetic ester MQL oils have been tested. The influences of wheel and coolant-lubricant types have been studied on the basis of the grinding forces, surface topography, and surface temperature. Synthetic ester MQL oil was found to give better grinding performance than the vegetable MQL oils. It was argued that the improved performance of the ester oil is caused by the formation of tribo-films on the abrasives and the workpiece, which enhances lubrication by inhibiting metal-abrasive interaction. Also, the grindability of the machined specimens was found to increase substantially by using the MQL grinding process with soft and coarse wheels. In MQL grinding of AA6061 alloy, the use of vegetable oil resulted in the lowest surface roughness, whereas using synthetic ester additives lead to highest surface roughness because of higher chip loading on the grinding wheel and consequently more redeposited material on the workpiece surface. © 2013 Springer-Verlag London.


Shabanian Boroujeni F.,Islamic Azad University at Dehaghan
Advances in Environmental Biology | Year: 2013

This paper examines the profitability or lossof charge and discharge automation system of new DRI silos of Mobarakeh Steel Company. In fact, the main objective of this research is to determine the economic quality of project in the automation system of unit (06) of Mobarakeh Steel complex during 2012-2013.In this study, 105 activities along with network transpositions have been studied. Project profitability and loss indicators (ACWP, BCWP and CPI) are calculated according to weight Factor of activities and their percent of completion, and project quality is economically reviewed. Results indicate that the cost performance index in all the activities is smaller than 1, and this shows that the project is already associated with loss and providing ways to minimize loss is inevitable. © 2013 AENSI Publisher All rights reserved.


Allameh M.,University of Isfahan | Zamani M.,University of Isfahan | Davoodi S.M.R.,Islamic Azad University at Dehaghan
Procedia Computer Science | Year: 2011

Today knowledge is considered as a valuable key in competition. Not only it is known as the foundation for stable development, but also it is the source of keeping competitive nature of an organization which is an advantage for the organization. The two fold role of culture, both as the main obstacle and also as the empowering factor in knowledge management activities, makes the importance of this factor double in efficient managing of knowledge management processes. The present article is examining any kind of relationship between different kinds of organizational culture and different dimension of knowledge management. In order to analyze differences between different organizational cultures, the proposed conceptual framework by Comeron and Quinn has been used here. In this article the relationship between four kinds of organizational culture which are group, developmental, hierarchical and logical (market) culture and six dimensions of knowledge management has been examined. This project is applied in nature and the methodology which has been used is correlationnal-descriptive; it is categorized as field study. For analyzing the findings of the research and accepting or rejecting the proposed hypothesis, statistical techniques like step by step regression as well as pearson correlationnal coefficienal has been used. The results indicated that there is a meaningful relationship (about 99%) between different kinds of organizational culture and six dimensions of knowledge management. © 2010 Published by Elsevier Ltd.


Allameh S.M.,University of Isfahan | Zare S.M.,University of Isfahan | Davoodi S.M.R.,Islamic Azad University at Dehaghan
Procedia Computer Science | Year: 2011

The main purpose of this research is to study the relationship between enablers as independent variable and knowledge management as dependent variable. The main hypothesis in this study is that the enablers are significantly related to knowledge management processes and improving the condition of enablers in organization leads to efficiency of knowledge management processes. In this research, Lawson's model for measuring knowledge management processes, and Lee and Choi's model for measuring the enablers are used. The findings of this study in employee's population accept the main and secondary hypotheses and show that enablers were significantly related to knowledge management processes. Technology and culture variables significantly were related to knowledge management processes and structure variable was not significantly related to knowledge management processes. Among the three enablers, technology and culture have the most effect on the knowledge management processes respectively. © 2010 Published by Elsevier Ltd.


Atefi R.,Islamic Azad University at Dehaghan | Razmavar A.,Islamic Azad University at Dehaghan | Teimoori F.,Islamic Azad University at Dehaghan
Life Science Journal | Year: 2012

This paper describes the processing and characterization of a new class of epoxy matrix composites reinforced with short fibers obtained from the scales of a fresh water fish (Labeo rohita). The functional groups involved in the formation of the resulting composite are identified. Fourier Transform Infrared (FTIR) spectroscopic analysis shows that the formation of hydrogen bonds occurring at the fiber-matrix interface between the oxygen atom of the epoxy and hydrogen atom of the polypeptide chain of fish scale is responsible for the formation of this new class of composites. These composites possess improved micro-hardness and exhibit tensile and flexural strengths marginally different from those of neat epoxy. These composites are expected to find applications as potential materials for conveyor belt rollers, pipes carrying pulverized coal in power plants, pump and impeller blades and also as low cost housing materials. © 2012. Zhengzhou University, Marsland Press.


Bagheri E.,Islamic Azad University at Dehaghan
International Review on Computers and Software | Year: 2011

In this paper we propose an agent-based conceptual and computational model for acceptance and transmission of word-of-mouth in a virtual society. We operationalized two dimensions of Hofstede national culture model: power distance and individualism in agent model. The model includes two important modules 'Update the Beliefs' and 'Decision to Do WOM', which are related to accepting and transmitting the word-of-mouth, respectively. Also, there is a state variable which includes the agents' beliefs about different topics which is affected by 'Update the Beliefs' module and will affect the ' Decision to Do WOM' module. Three scenarios are considered to test the model: in large power distance, high collectivism, and high individualism and small power distance cultures. Our results represent that trust is of high importance in small power distance and high individualism cultures, group values is very important in collectivistic cultures and social status has a great influence on word-of-mouth acceptance and transmission in large power distance cultures. © 2011 Praise Worthy Prize S.r.l.-All rights reserved.

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