2009
16
1
1
0
http://scientiairanica.sharif.edu/3192.html
Multi Attribute Decision Making on InterBasin Water Transfer Projects
2
2
One of the best ways to control water shortages in the Central Region of Iran is interbasin water transfer (IBWT). Efficient decision making on this subject is however a real challenge for the water authorities in Iran. These decisions should include multiple attributes, model uncertainty, and also the optimistic/pessimistic view of the decision makers.
The Ordered Weighted Averaging (OWA) operator can be used as an efficient multi attribute decision making (MADM) method. This paper will introduce a new method to obtain the order weights of this operator. The new method is based on the combination of fuzzy quantifiers and neat OWA operators. Fuzzy quantifiers are applied for soft computing in modeling the optimism degree of the decision maker. In using neat operators, the ordering of the inputs is not needed resulting in better computation efficiency. The theoretical results will be illustrated in a case study by solving an MADM problem with four IBWT projects for the Zayanderud basin. The results demonstrate that more sensitive decisions can be obtained by using the new method.
2

0
0


M.
Zarghami
Department of Industrial Engineering,Sharif University of Technology
Iran
zxazeehm@scientiaunknown.non


R.
Ardakanian
Department of Industrial Engineering,Sharif University of Technology
Iran
hkasrhyo@scientiaunknown.non


F.
Szidarovszky
Department of Systems and Industrial Engineering,University of Arizona
Iran
email@email.com
http://scientiairanica.sharif.edu/3193.html
A Hybrid Scatter Search for the ResourceConstrained Project Scheduling Problem
2
2
Abstract
In this paper we develop a new hybrid metaheuristic algorithm based on the scatter search approach to solve the wellknown resourceconstrained project scheduling problem. This algorithm combines two solutions from scatter search to build a set of precedence feasible activity lists and select some of them as children for the new population. We use the idea presented in the forward/backward improvement technique to define two types of schedule, direct and reverse, and the members of the sequential populations change alternately between these two types of schedule. Extensive computational tests were performed on standard benchmark datasets and the results are compared with the best available results. Comparative computational tests indicate that our procedure is a very effective metaheuristic algorithm.
2
Abstract
In this paper we develop a new hybrid metaheuristic algorithm based on the scatter search approach to solve the wellknown resourceconstrained project scheduling problem. This algorithm combines two solutions from scatter search to build a set of precedence feasible activity lists and select some of them as children for the new population. We use the idea presented in the forward/backward improvement technique to define two types of schedule, direct and reverse, and the members of the sequential populations change alternately between these two types of schedule. Extensive computational tests were performed on standard benchmark datasets and the results are compared with the best available results. Comparative computational tests indicate that our procedure is a very effective metaheuristic algorithm.
Keywords: Project scheduling; Metaheuristic; Scatter search
0
0


M.
Ranjbar
Department of Industrial Engineering,Sharif University of Technology
Iran
m_ranjbar@mehr.sharif.edu


F.
Kianfar
Department of Industrial Engineering,Sharif University of Technology
Iran
kianfar@sharif.edu
Project scheduling
Metaheuristic
Scatter Search
http://scientiairanica.sharif.edu/3194.html
Replacement–repair policy based on simulation model for multistate deteriorating products under warranty
2
2
Abstract
In this paper a replacementrepair model is developed to study a warranty servicing policy for a class of multistate deteriorating and repairable products based on a computer simulation analysis. In each working state there is a determined probability for transition to each of the subsequent states, given that it has made a transition out of that state. There are two parameters that determine the manufacturer’s decision to repair or replace a failed item assuming that buyer’s claim is valid, the deterioration degree of the item and the length of the residual warranty period. Beside these two parameters, other inputs to the model are; the number of working and failure states, the different rates of transition from each working state given that the life distribution is exponential, the length of entire warranty period, the probabilities of transition between states, the cost of repair and replacement in each failure state. The output of the model is the mean and standard deviation of the total simulated costs generated for a given set of inputs and such that the best values of the two mentioned parameters can be obtained based on the statistical test. The model is validated by comparing its output with the optimal expected costs generated by a mathematical approach for a few special situations where this comparison is possible.
2
Abstract
In this paper a replacementrepair model is developed to study a warranty servicing policy for a class of multistate deteriorating and repairable products based on a computer simulation analysis. In each working state there is a determined probability for transition to each of the subsequent states, given that it has made a transition out of that state. There are two parameters that determine the manufacturer’s decision to repair or replace a failed item assuming that buyer’s claim is valid, the deterioration degree of the item and the length of the residual warranty period. Beside these two parameters, other inputs to the model are; the number of working and failure states, the different rates of transition from each working state given that the life distribution is exponential, the length of entire warranty period, the probabilities of transition between states, the cost of repair and replacement in each failure state. The output of the model is the mean and standard deviation of the total simulated costs generated for a given set of inputs and such that the best values of the two mentioned parameters can be obtained based on the statistical test. The model is validated by comparing its output with the optimal expected costs generated by a mathematical approach for a few special situations where this comparison is possible.
Keywords: warranty; multistate; simulation; deteriorating product.
0
0


A.
Eshraghnia Jahromi
Department of Industrial Engineering,Sharif University of Technology
Iran
eshragh@sharif.edu


H.
Vahdani
Department of Industrial Engineering,Sharif University of Technology
Iran
ivepwsti@scientiaunknown.non
warranty
multistate
Simulation
deteriorating product
http://scientiairanica.sharif.edu/3195.html
Investigation of Impact of Supply Chain Integration on Product Innovation and Quality
2
2
Abstract
This paper addresses integration issues in supply chain, and tries to investigate how different aspects of integration are linked with some product features. Integration in this study is interpreted as "internal", "upstream" (supply), and "downstream" (demand). Two product features which are considered in this study are "product innovation" and "product quality". To examine the relationships between supply chain integrations – as mentioned above, and product features, this research follows the survey method in automotive industry.
The results imply that comparing to internal and supply chain downstream integrations supply chain upstream integration has a higher impact on product quality. It is also found that the influence of supply chain downstream integration on product innovation is greater than other variables. In brief, this study mainly tackles the importance of specific level of supply chain integrations and its effects on two product features.
2
Abstract
This paper addresses integration issues in supply chain, and tries to investigate how different aspects of integration are linked with some product features. Integration in this study is interpreted as "internal", "upstream" (supply), and "downstream" (demand). Two product features which are considered in this study are "product innovation" and "product quality". To examine the relationships between supply chain integrations – as mentioned above, and product features, this research follows the survey method in automotive industry.
The results imply that comparing to internal and supply chain downstream integrations supply chain upstream integration has a higher impact on product quality. It is also found that the influence of supply chain downstream integration on product innovation is greater than other variables. In brief, this study mainly tackles the importance of specific level of supply chain integrations and its effects on two product features.
Keywords: Supply chain upstream integration, supply chain downstream integration, internal integration, product features
0
0


S. R.
Hosseini Baharanchi
Department of Industrial Engineering,Azad University
Iran
srhb.1342@yahoo.com
Supply chain upstream integration
supply chain downstream integration
internal integration
product features
http://scientiairanica.sharif.edu/3196.html
Designing an Optimum Acceptance Sampling Plan Using Bayesian Inferences and Stochastic Dynamic Programming Approach
2
2
Abstract
In this paper, we use both the stochastic dynamic programming and Bayesian inferences concepts to design an optimumacceptancesamplingplan policy in quality control environments. To determine the optimum policy we employ a combination of costs and risk functions in the objective function. Unlike previous studies, accepting or rejecting a batch are directly included in the action space of the proposed dynamic programming model. Using the posterior probability of the batch to be in state p (the probability of nonconforming products), first we formulate the problem into a stochastic dynamic programming model. Then, we derive some properties for the optimal value of the objective function, which enable us to search for the optimal policy that minimizes the ratio of the total discounted system cost to the discounted system correct choice probability.
2
Abstract
In this paper, we use both the stochastic dynamic programming and Bayesian inferences concepts to design an optimumacceptancesamplingplan policy in quality control environments. To determine the optimum policy we employ a combination of costs and risk functions in the objective function. Unlike previous studies, accepting or rejecting a batch are directly included in the action space of the proposed dynamic programming model. Using the posterior probability of the batch to be in state p (the probability of nonconforming products), first we formulate the problem into a stochastic dynamic programming model. Then, we derive some properties for the optimal value of the objective function, which enable us to search for the optimal policy that minimizes the ratio of the total discounted system cost to the discounted system correct choice probability.
Keywords: Quality inspection; Acceptance sampling plan; Bayesian inference; Stochastic Dynamic programming
0
0


S.T.
Akhavan Niaki
Department of Industrial Engineering,Sharif University of Technology
Iran
niaki@sharif.edu


M. S.
Fallah Nezhad
Department of Industrial Engineering,Sharif University of Technology
Iran
fallahnezhad@mehr.sharif.edu
Quality inspection
Acceptance sampling plan
Bayesian inference
Stochastic Dynamic programming
http://scientiairanica.sharif.edu/3197.html
Robot Movements in a cyclic multiplepart type Threemachine Flexible Robotic Cell problem
2
2
Abstract
This paper recognizes thirtysix potentially optimal robot movement policies to schedule, movements of a robot in a threemachine flexible cell. The robotic cell produces multitype parts in which the robot is used as material handling system. In this manufacturing cell the machines have operational flexibility and can be set up for different operations, and all parts have three operations. Finding the robot movement policy and sequence of parts to minimize cycle time (i.e.; maximize the throughput) is the aim of this work. It was proved that cycle time calculation in twelve policies out of thirtysix policies, are unary NPcomplete, and a polynomial time algorithms is introduced that can solve the twentyfour left policies. This paper develops cycle times of all these thirty six robot movements policies where considering waiting times in a flexible three machine robotic cell with multitype parts, and introduces parts sequence in a special condition that one of the policies minimize the cycle time (i.e. maximize throughput). This kind of flexibility is differing from the other researches in robotic cells that a machine can process different operations, moreover we consider cells with multiple part types which is more realistic than other developed models.
Finally a new mathematical model based on Petri nets provided, for one of robot movement policies. Further this mathematical model is developed for the multitype part problem.
2
Abstract
This paper recognizes thirtysix potentially optimal robot movement policies to schedule, movements of a robot in a threemachine flexible cell. The robotic cell produces multitype parts in which the robot is used as material handling system. In this manufacturing cell the machines have operational flexibility and can be set up for different operations, and all parts have three operations. Finding the robot movement policy and sequence of parts to minimize cycle time (i.e.; maximize the throughput) is the aim of this work. It was proved that cycle time calculation in twelve policies out of thirtysix policies, are unary NPcomplete, and a polynomial time algorithms is introduced that can solve the twentyfour left policies. This paper develops cycle times of all these thirty six robot movements policies where considering waiting times in a flexible three machine robotic cell with multitype parts, and introduces parts sequence in a special condition that one of the policies minimize the cycle time (i.e. maximize throughput). This kind of flexibility is differing from the other researches in robotic cells that a machine can process different operations, moreover we consider cells with multiple part types which is more realistic than other developed models.
Finally a new mathematical model based on Petri nets provided, for one of robot movement policies. Further this mathematical model is developed for the multitype part problem.
Keywords: Production Scheduling, Cyclic blocking Open shop, Flexible Robotic Cell
0
0


S.
Gholami
Department of Industrial Engineering,Tarbiat Modares University
Iran
gholams@modares.ac.ir


I.N.
Kamal Abadi
Department of Industrial Engineering,Kuwait University
Iran
nakhai_isa@yahoo.com
Production Scheduling
Cyclic blocking Open shop
Flexible Robotic Cell
http://scientiairanica.sharif.edu/3198.html
A branch and bound algorithm for the weighted earlinesstardiness project scheduling problem with generalized precedence relations
2
2
Abstract
We present an exact solution procedure for the weighted earlinesstardiness project scheduling problem (WETPSP) with generalized precedence relations (WETPSPGPR), taking into account time value of money (WETPSPDCGPR) and a fixed deadline for the project. The WETPSPGPR extends the WETPSP to arbitrary minimal and maximal timelags between the starting and completion times of activities. We present a new depthfirst branch and bound (B&B) algorithm for extended form of the problem, which time value of money is taken into account by discounting the cash flows and minimum as well as maximum timelags between different activities may be given. The algorithm is extended with two bounding rules in order to reduce the size of the branch and bound tree. Finally, some test problems are solved and computational results are reported.
2
Abstract
We present an exact solution procedure for the weighted earlinesstardiness project scheduling problem (WETPSP) with generalized precedence relations (WETPSPGPR), taking into account time value of money (WETPSPDCGPR) and a fixed deadline for the project. The WETPSPGPR extends the WETPSP to arbitrary minimal and maximal timelags between the starting and completion times of activities. We present a new depthfirst branch and bound (B&B) algorithm for extended form of the problem, which time value of money is taken into account by discounting the cash flows and minimum as well as maximum timelags between different activities may be given. The algorithm is extended with two bounding rules in order to reduce the size of the branch and bound tree. Finally, some test problems are solved and computational results are reported.
Keywords: Project scheduling; Branch and bound; Net present value; generalized precedence relations
0
0


B.
Afshar Nadjafi
Department of Industrial Engineering,Sharif University of Technology
Iran
afsharnb@mehr.sharif.edu


S.
Shadrokh
Department of Industrial Engineering,Sharif University of Technology
Iran
shadrokh@sharif.edu
Project scheduling
Branch and Bound
Net Present Value
generalized precedence relations
http://scientiairanica.sharif.edu/3199.html
Service Quality Prioritization in various environments (A Crosscultural comparison)
2
2
Abstract
The findings of this research are mostly useful to those who intend to penetrate international “Business to Consumer” markets. One of the key challenges of online businesses is how they manage service quality, which holds a significant importance to customer satisfaction. This paper is purposed to unveil customers’ perceptions on service quality priority and different cultures’ expectations in online shopping. The questionnaire utilized, was based on the SERVQUAL instrument that identifies five quality dimensions. This study indicates that in the developing countries customers need more security and clarity in transactions. The managerial and theoretical implications are provided.
Key Words: Electronic commerce, online retailing, service quality.
2

0
0


A.
Albadvi
Department of Industrial Engineering,Tarbiat Modares University
Iran
email@email.com


R.
Mostaghel
Department of Industrial Engineering,Tarbiat Modares University
Iran
http://scientiairanica.sharif.edu/3200.html
Special Classes of Fuzzy Integer Programming Models with Alldifferent Constraints
2
2
Abstract: In this paper, a fuzzy approach is applied to special classes of integer programming problems with all different constraints. In the first model, a fuzzy integer programming model is developed to represent the alldifferent constraints in mathematical programming. In order to solve the proposed model, a new branching scheme for the B&B algorithm is also presented. In the second model, a special class of largescale multiobjective fuzzy integer programming problems with alldifferent constraints is introduced. A solution method for the proposed model is also developed by using the decomposition technique, weighting method and B&B algorithm. An illustrative numerical example is also given to clarify the theory and the method discussed in this paper.
2
Abstract: In this paper, a fuzzy approach is applied to special classes of integer programming problems with all different constraints. In the first model, a fuzzy integer programming model is developed to represent the alldifferent constraints in mathematical programming. In order to solve the proposed model, a new branching scheme for the B&B algorithm is also presented. In the second model, a special class of largescale multiobjective fuzzy integer programming problems with alldifferent constraints is introduced. A solution method for the proposed model is also developed by using the decomposition technique, weighting method and B&B algorithm. An illustrative numerical example is also given to clarify the theory and the method discussed in this paper.
Keywords: Fuzzy integer programming, alldifferent constraints, Branch & Bound algorithm
0
0


J.
Nematian
Department of Industrial Engineering,Sharif University of Technology
Iran
nematian@mehr.sharif.edu


K.
Eshghi
Department of Industrial Engineering,Sharif University of Technology
Iran
eshghi@sharif.edu
Fuzzy integer programming
alldifferent constraints
Branch & Bound algorithm