Laya Olfat; Maghsoud Amiri; Ebrahim Teimoury; Fatemeh Ghasemzadeh Gevari
Abstract
In today’s competitive world, supply chain management gains more attention every day. One of the most challenging topics in this field for managers and researchers is supply chain disruption management. When a disruption occurs in an echelon of a multi level supply chain, it may affect other echelon’s ...
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In today’s competitive world, supply chain management gains more attention every day. One of the most challenging topics in this field for managers and researchers is supply chain disruption management. When a disruption occurs in an echelon of a multi level supply chain, it may affect other echelon’s performance in that supply chain as well. The main objective of current research is helping decision makers to choose best supply, production and ordering quantity between echelons so that after disruption occurrence, SC recovers and returns to pre-disruption plan with minimum recovering costs.In this paper, production and retailers disruptions are studied and a mathematical recovery plan is designed with objective function of minimizing total cost of supply chain in the recovery period to help all members of the supply chain in returning to normal situation. The proposed model is solved in MATLAB 2011 by the suggested heuristic method as well as GAMS software. Finally, results of both solvers are compared which shows the applicability of heuristic method
Laya Olfat; Maghsod Amiri; Ahmad Jafarian
Abstract
Cross-docking is one of the lean logistics tools that is used for uniting the shipments during the loops replacement. Cross-docking is the process of product movement form distribution centers without storage function. Vehicle routing problem in Cross-Dock external environment has much influence on cross-dock ...
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Cross-docking is one of the lean logistics tools that is used for uniting the shipments during the loops replacement. Cross-docking is the process of product movement form distribution centers without storage function. Vehicle routing problem in Cross-Dock external environment has much influence on cross-dock costs. This paper provides a model for minimizing total distance traveled by vehicles in the external environment of a cross-dock. In this paper, Vehicles routes was modeled with capacitated vehicle routing problem (CVRP) and genetic algorithm (GA) was used to solve the model. To validate responses obtained by GA, simulated annealing (SA) was used. Also, to evaluate the efficacy of two algorithms (SA & GA) in different CVRP problems in cross-dock, 10 problems with different dimensions are evaluated. The results show that in problems with smaller size GA is more efficient, whereas in large size problems SA is more efficient
Roozbeh . Azizmohammadi; Maghsoud .Amiri; Reza Tavakkoli- Moghadam; Hamid Reza. Mashatzadegan
Volume 14, Issue 42 , October 2016, , Pages 103-121
Abstract
A redundancy allocation problem is a well-known NP-hard problem thatinvolves the selection of elements and redundancy levels to maximize thesystem reliability under various system-level constraints. In many practicaldesign situations, reliability apportionment is complicated because of thepresence of ...
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A redundancy allocation problem is a well-known NP-hard problem thatinvolves the selection of elements and redundancy levels to maximize thesystem reliability under various system-level constraints. In many practicaldesign situations, reliability apportionment is complicated because of thepresence of several conflicting objectives that cannot be combined into asingle-objective function. A stele communications, manufacturing and powersystems are becoming more and more complex, while requiring shortdevelopments schedules and very high reliability, it is becoming increasinglyimportant to develop efficient solutions to the RAP. In this paper, a newhybrid multi-objective competition algorithm (HMOCA)based oncompetitive algorithm (CA) and genetic algorithm (GA) is proposed for thefirst time in multi-objective redundancy allocation problems. In the multiobjectiveformulation, the system reliability is maximized while the cost andvolume of the system are minimized simultaneously. Additionally, ay RSMis employed to tune the CA parameters. The proposed HMOCA is validatedby some examples with analytical solutions. It shows its superiorperformance compared to a NSGA-II and PAES algorithms. Finally, theconclusion is given
Yalda Yahyazade; Laya Olfat; Maghsod Amiri
Abstract
Appropriate management of supply chain is one of the issues facing economic firms that affect all the organizational activities in order to produce the goods and provide the services. Consequently Supplier selection due to involvement of various qualitative and quantitative criteria such as quality, ...
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Appropriate management of supply chain is one of the issues facing economic firms that affect all the organizational activities in order to produce the goods and provide the services. Consequently Supplier selection due to involvement of various qualitative and quantitative criteria such as quality, price, flexibility and delivery times is very difficult and complex and requires accurate and appropriate tools. On the other hand today's competitive environment due to its variable nature, has added the uncertainty and ambiguity in decision-making. The problem of supplier selection is not an exception as well and it seems suitable to use the robust optimization methods in such circumstances. The mentioned method is used in this research with the goal of supplier selecting and determining the amount order of products considering all restrictions in order to minimize the costs and maximize the utility of purchase in the condition of uncertainty. In this paper, a multi-objective deterministic model is presented to solve the problem, and then the deterministic model is converted to the robust model using the scenario-based robust method and then is solved using the LP metric method so optimal amount of order is obtained from each of suppliers at any period. To determine the weight of each of suppliers, Analytical Hierarchy Process (AHP) is used as well.
Reza Abasi; Jamshid Salehi Sadaghiani; Maghsoud Amiri
Volume 13, Issue 38 , October 2015, , Pages 79-98
Abstract
There are several different factors in industrial processes, which may have an impact on final product specifications. In this paper, the nonlinear multi-objective mathematical modeling for the 5 qualitative characteristics of polyethylene terephthalate (PET) as one of the most widely used products in ...
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There are several different factors in industrial processes, which may have an impact on final product specifications. In this paper, the nonlinear multi-objective mathematical modeling for the 5 qualitative characteristics of polyethylene terephthalate (PET) as one of the most widely used products in petrochemical industry is done by 9 Key parameters affecting the production process. For this purpose, Response Surface Methodology that is the combination of experiments design and statistical tests is applied along with Artificial Neural Network and Metaheuristic algorithms.
Magsud Amiri; , Mohammad Amin Nayebi; Oveis Zarabadipour
Volume 12, Issue 33 , July 2015, , Pages 125-124
Abstract
In this paper we have developed inventory control models (r,Q) & (R,T) in multi-items environment by two objectives as minimizing costs (holding & shortage) and risk level under four constraints. These constraints include: available budge, service level, storage space & allowed shortage quantities. ...
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In this paper we have developed inventory control models (r,Q) & (R,T) in multi-items environment by two objectives as minimizing costs (holding & shortage) and risk level under four constraints. These constraints include: available budge, service level, storage space & allowed shortage quantities. Demand functions assumed normal in the study and extra demands also are backlogged. First we developed crisp models and then fuzzy stochastic models with fuzzy budge, allowed shortage quantities and shortage space which are fuzzy-stochastic parameters with normal distribution. All of fuzzy numbers are triangular typically. In this methodology we changed fuzzy-stochastic models to crisp multi objectives problem, by using difuzzification of fuzzy constraints and then solving by Fuzzy logic method. Finally we have tested an example to describe the model and methodology which is solved by LINGO package. .
Maghsoud Amiri; Mahdi Keshavarz Gharabaei
Volume 13, Issue 36 , April 2015, , Pages 143-171
Abstract
Actual scheduling problems may necessitate the decision maker to consider a variety of criteria prior to make any decision. This research considers a single machine scheduling problem, with the objective of minimizing a combination of total tardiness and waiting time variance criteria in which the idle ...
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Actual scheduling problems may necessitate the decision maker to consider a variety of criteria prior to make any decision. This research considers a single machine scheduling problem, with the objective of minimizing a combination of total tardiness and waiting time variance criteria in which the idle time is not allowed. Minimizing total tardiness is always regarded as one of the most important performance criteria in practical systems to avoid penalty costs of tardiness and waiting time variance is an important criterion in establishing Quality of Service (QoS) in many systems. Each of these criteria is known to be NP-hard and therefore the linear combination of them will be NP-hard as well. For this problem, we developed a genetic algorithm by utilizing its general structure. Two types of heuristic and random initial population and two distinct fitness functions are applied to genetic algorithms. The GA is shown experimentally to perform well by testing on various instances.
maghsoud amiri; laya olfat; amir hasanzadeh
Volume 11, Issue 29 , July 2013, , Pages 89-112
Abstract
A major cause of supply chain deficiencies is the bullwhip effect. This phenomenon refers to demand variability increases as one move up the supply chain. Supply chain managers experience this variance amplification in both inventory levels and orders. Other side, dampening variability in orders may ...
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A major cause of supply chain deficiencies is the bullwhip effect. This phenomenon refers to demand variability increases as one move up the supply chain. Supply chain managers experience this variance amplification in both inventory levels and orders. Other side, dampening variability in orders may have a negative impact on customer service due to increase in inventory variance. The contribution of this paper is the estimation of the bullwhip effect and stock functions with using of response surface method under causes of the bullwhip effect in a three stage supply chains consisting of a single retailer, single wholesaler and single manufacturer with both centralized and un-centralized chains and show that with Considering the importance of the bullwhip effect reasons and interactions between them, the percent of optimal reasons and interactions between them and the level of desirability of bullwhip effect and net Stock will be illustrated by a model
Maghsoud Amiri; Mohsen Rahimi Mazrae shahi; Hamid Taboli
Volume 9, Issue 24 , March 2012, , Pages 45-65
Abstract
This article suggests a new method for solving multi-criteria decision making issues. The method has been designed by simple but rational mathematical logic based on a specific geometric definition of the options. Understandable content as well as algorithm simplicity and simplified process are the rich ...
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This article suggests a new method for solving multi-criteria decision making issues. The method has been designed by simple but rational mathematical logic based on a specific geometric definition of the options. Understandable content as well as algorithm simplicity and simplified process are the rich standing points of the approach. Such problems have always had a brand-new geometric approach whilst the calculations involved in this method are benefiting from the lack of complex and complicated steps and the essential patronized path. Categorizing the enriched method's significances, we may finally come up with the availability of graphical model provided for the users. The users are properly enabled to enlighten presenting a geometric logic.
Laya Olfa; ahanyar BamdadSoofu; Maghsoud Amir; Mostafa Ebrahimpoor Azbari
Volume 10, Issue 26 , January 2012, , Pages 9-34
Abstract
For performance evaluation of supply chain, having a comprehensivemodel with reliable data is useful. This can help to improve the entirechain. In this paper a model is presented, according to the nature ofnetwork and multi-stage supply chain, that able to evaluate theperformance of the entire chain ...
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For performance evaluation of supply chain, having a comprehensivemodel with reliable data is useful. This can help to improve the entirechain. In this paper a model is presented, according to the nature ofnetwork and multi-stage supply chain, that able to evaluate theperformance of the entire chain in the form of a mathematical modeland using the financial, knowledge, participation and responsemeasures of the supply chain. In the first part, Indicator sat threelevels; strategic, process and operational, considered and survey themodel verification with Factor Analysis. In the second part, Networkdata envelopment analysis model is used. This paper is the result ofresearch related to supply chain of pharmaceutical companies inTehran Stock Exchange and 115 expert sand senior executive shavebeen questioned as sample. There search results show that strategiclevel with a weight of 0.98 is the most important performance leveland Process and operational levels are respectively 0.97 and 0.87weight. 4chainsof 28 chains studied, have a complete performance and0.43 is the lowest observed performance.
Abolfazl Kazzazi; Maghsood Amiri; Fatemeh Rahbar Yaghoobi
Volume 8, Issue 20 , March 2011, , Pages 49-79
Abstract
In This paper, application of MCDM techniques in evaluation and ranking of Temad Co. strategies has been considered. Statistical target group, as "expert group" has been chosen among company's managers to identify strategies and evaluate them. At the first phase, strategies have been deducted with SWOT ...
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In This paper, application of MCDM techniques in evaluation and ranking of Temad Co. strategies has been considered. Statistical target group, as "expert group" has been chosen among company's managers to identify strategies and evaluate them. At the first phase, strategies have been deducted with SWOT technique and at the second phase, they have been ranked by ELECTR III technique. Criteria for evaluating strategies gathered among different resources and got summarized according to strategic experts' ideas. Weight of criteria has determined by RTC or PCT technique and thresholds have been dedicated by decision makers. To reduce uncertainty of decision making, ranking has been done in fuzzy situation. Furthermore, for assessing efficiency of results, sensitivity analysis has been implemented with two approaches. According to final results, evaluation and ranking of strategies can be done well by means of ELECTRE III technique.
Maghsoud Amiri
Volume 8, Issue 18 , September 2010, , Pages 15-39
Abstract
Some problems of real world, must be determine and analyze input variable's effect on response variable. One of the applicable techniques which are used for modeling and solving such problems is response surface methodology (RSM). In this paper the effect of five controllable input factors: raw materials, ...
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Some problems of real world, must be determine and analyze input variable's effect on response variable. One of the applicable techniques which are used for modeling and solving such problems is response surface methodology (RSM). In this paper the effect of five controllable input factors: raw materials, electromotor speed, stove temperature, furnace temperature and air pressure on the determined response surface level i.e. the resistance of glass bottle is checked by design of experiment (DOE). After the execution of experiments and the recognition of effective factors, according to the application of RSM, the relationship between variables of effective input factors and the response surface variable is determined by nonlinear regression model. Then, the optimal value of each variable in nonlinear model is obtained by goal programming method.
Maghsoud Amiri; Amir Alimi; Seyed Hossein Abtahi
Volume 6, Issue 17 , September 2007, , Pages 135-151
Abstract
Data envelopment analysis model is a model for calculating the efficiency of decision making units (DMUs). In previous models there are some weaknesses that the most important one is changing weights of inputs and outputs in model that lead to evaluate efficiencies of DMUs with different weights. The ...
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Data envelopment analysis model is a model for calculating the efficiency of decision making units (DMUs). In previous models there are some weaknesses that the most important one is changing weights of inputs and outputs in model that lead to evaluate efficiencies of DMUs with different weights. The important subject is that How we should evaluate all of decision making units with one set of weights and optimize their efficiencies simultaneously. This paper aims to present a new model that eliminates the weaknesses of previous models. Odeveloped model is designed based on multi objective decision making models and this model is solved with fuzzy solution method of multi objective decision making models and leads to creating common weights. The main object of research that was better ranking of DMUs rather than basic models have been done by using this model and this is showed with solving the model on an example.
Maghsoud Amiri
Volume 6, Issue 16 , June 2007, , Pages 167-188
Abstract
Selection of appropriate machine tools for a manufacturing company, because that effects on product process, is a very important. But by imprecise information, the selection will be complicated. The VIKOR method is one of new methods for solving problems of multiple criteria decision making where its ...
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Selection of appropriate machine tools for a manufacturing company, because that effects on product process, is a very important. But by imprecise information, the selection will be complicated. The VIKOR method is one of new methods for solving problems of multiple criteria decision making where its objective is selecting the best alternative based on the closest feasible solution to the ideal solution. In this article will be proposed a fuzzy approach for the VIKOR method where rating alternatives and importance weights of criteria are considered as fuzzy numbers. Also in the proposed method, importance weight of DMs thoughts is considered different. For illustrating the proposed method, a numerical example about machine tools selection has been presented for illustrating the proposed method, where criteria of alternatives evaluation are flexibility, confidence ability and maintainability of machines.
Maghsoud Amiri
Volume 6, Issue 15 , March 2007, , Pages 143-165
Abstract
After introducing Markowitz mean-variance model, decision makers (DMs) and financial planners paid much attention to the matter of portfolio selection, so that DMs explain purposes and investment requirements in the frame of multi-objective mathematic models which are more consistent with decision making ...
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After introducing Markowitz mean-variance model, decision makers (DMs) and financial planners paid much attention to the matter of portfolio selection, so that DMs explain purposes and investment requirements in the frame of multi-objective mathematic models which are more consistent with decision making realities in optimal portfolio selection. At now there are various methods introduced to optimize such problems. One of the optimization methods is the Compromise Programming (CP) method. In this paper, considering increasing importance of investment in financial portfolios, we propose a new method, called Nadir Compromising Programming (NCP) by expanding a CP-based method for optimization of multi-objective portfolio selection problem. In order to examine NCP performance and operational capability, we implemented a case study by selecting a portfolio with 35 stock indices of Iran stock market. Results of comparing the CP method and proposed method under the same conditions indicate that NCP method results are more consistent with DM purposes.
Maghsoud Amiri; Sara Hatami; Seyed Mostafa Moosavi
Volume 5, Issue 14 , December 2006, , Pages 251-273
Abstract
In this paper we try to determine optimal combination of effective factors to produce cattle feed. Cattle feed has direct relation with cattle health, this research is done on real case study, therefore the gained results could be too important. Both response surface methodology and design of experiments ...
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In this paper we try to determine optimal combination of effective factors to produce cattle feed. Cattle feed has direct relation with cattle health, this research is done on real case study, therefore the gained results could be too important. Both response surface methodology and design of experiments are used for modeling and improving cattle feed production process which has more than one effective factor. After effective factors identification, designing of experiments will be done by central composite design. Interference factors, effective and independent parameters are inspected by forward method and finally a model is obtained by independent parameters. Because of continuous space of the problem and nonlinear objective functions a metaheuristics named "genetic annealing" is used to solve the problem. Proposed algorithm searched the solution space parallel. Another algorithm, simulated annealing is also proposed to evaluate the performances of two algorithms by improvement percent between initial and final result.
Maghsood Amiri; Mostafa Jafarian; Sara Hatami
Volume 4, Issue 12 , March 2006, , Pages 1-43
Abstract
This paper extends a kind of evaluation process based on fuzzy TOPS IS approach. By focusing on determining the importance and weights of criteria which are effective on decision making , then selecting by lean on Anthropy and eigenvector methods in which comparison between criteria are linguistic and ...
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This paper extends a kind of evaluation process based on fuzzy TOPS IS approach. By focusing on determining the importance and weights of criteria which are effective on decision making , then selecting by lean on Anthropy and eigenvector methods in which comparison between criteria are linguistic and by achieving the weights we try to show the importance for criteria. The application and the mix of several methods in this paper are used to choose the best tickicide and to rank the available alternatives.
Maghsoud Amiri
Volume 3, Issue 9 , June 2005, , Pages 29-40
Abstract
In this paper we used the Markov models eigenvectors and eigen values concdpts to propose a methodology for analyzing the transient reliability of system with the identical components and the identical repairmen. The components of the systems under consideration can have two distinct configurations, ...
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In this paper we used the Markov models eigenvectors and eigen values concdpts to propose a methodology for analyzing the transient reliability of system with the identical components and the identical repairmen. The components of the systems under consideration can have two distinct configurations, namely ; they can be arranged in series, or in parallel. We also consider the third case in which the system is up if k –out –of – n components are good. For all three cases we proposed a procedure for calculating the transient probability of the system availability and the duration of the system to reach to the steady state are described.
Magbsood Amiri
Volume 2, Issue 7 , December 2004, , Pages 37-55
Abstract
One of the most important issues in inventory control is determination of the reorder point. Defining parameters of this point are usually in forms of crisp or probability. In this article the parameters are considered as fuzzy numbers because of ambiguities in the real world. Then reorder point ...
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One of the most important issues in inventory control is determination of the reorder point. Defining parameters of this point are usually in forms of crisp or probability. In this article the parameters are considered as fuzzy numbers because of ambiguities in the real world. Then reorder point value is calculated using a cut concept extension principle fuzzy arithmetic and fuzzy trapezoidal numbers. Finally concluding remarks are given.
