Esmaeil Mehdizadeh - Academia.edu (original) (raw)

Papers by Esmaeil Mehdizadeh

International Journal of Systems Science, 2013

A new mathematical model for the capacitated multi-facility location-allocation problem with prob... more A new mathematical model for the capacitated multi-facility location-allocation problem with probabilistic customers' locations and demands is developed in this paper. The model is formulated into the frameworks of the expected value model (EVM) and the chance-constrained programming (CCP) based on two different distance measures. In order to solve the model, two hybrid intelligent algorithms are proposed, where the simplex algorithm and stochastic simulation are the bases for both algorithms. However, in the first algorithm, named SSGA, a special type of genetic algorithm is combined and in the second, SSVDO, a vibration damping optimization (VDO) algorithm is united. The Taguchi method is employed to tune the parameters of the two proposed algorithms. Finally, some numerical examples are given to illustrate the applications of the proposed methodologies and to compare their performances.

2010 IEEE International Conference on Automation and Logistics, 2010

Abstract - Scheduling for the flexible job shop is very important in both fields of production ma... more Abstract - Scheduling for the flexible job shop is very important in both fields of production management and combinatorial optimization. However, when we attempt to formulate job shop scheduling problems which closely describe and represent the real world problem, various factors ...

Engineering review, 2018

This paper develops two mixed integer linear programming (MILP) models for an integrated aggregat... more This paper develops two mixed integer linear programming (MILP) models for an integrated aggregate production planning (APP) system with return products, breakdowns and preventive maintenance (PM). The goal is to minimize the cost of production with regard to PM costs, breakdowns, the number of laborers and inventory levels and downtimes. Due to NP-hard class of APP, we implement a harmony search (HS) algorithm and vibration damping optimization (VDO) algorithm for solving these models. Next, the Taguchi method is conducted to calibrate the parameter of the metaheuristics and select the optimal levels of factors influencing the algorithm’s performance. Computational results tested on a set of randomly generated instances show the efficiency of the vibration damping optimization algorithm against the harmony search algorithm. We find VDO algorithm to obtain best quality solutions for APP with breakdowns and PM, which could be efficient for large scale problems. Finally, the computati...

International Journal of Industrial Mathematics, 2016

This paper proposes a multi-supplier multi-product inventory model in which the suppliers have un... more This paper proposes a multi-supplier multi-product inventory model in which the suppliers have unlimited production capacity, allow delayed payment, and oer either an all-unit or incremental discount. The retailer can delay payment until after they have sold all the units of the purchased product. The retailers warehouse is limited, but the surplus can be stored in a rented warehouse at a higher holding cost. The demand over anite planning horizon is known. This model aims to choose the best set of suppliers and also seeks to determine the economic order quantity allocated to each supplier. The model will be formulated as a mixed integer and nonlinear programming model which is NP-hard and will be solved by using genetic algorithm (GA), simulated annealing (SA) algorithm, and vibration damping optimization (VDO) algorithm. Finally, the performance of the algorithms will be compared.

European Society for Fuzzy Logic and Technology, 2009

Muṭāli̒āt-i Mudīriyyat-i Ṣan̒atī, 2015

This paper presents a mathematical model for solving dynamic cell formation problem, operator ass... more This paper presents a mathematical model for solving dynamic cell formation problem, operator assignment and the inter-cellular and intra-cellular layouts simultaneously. The proposed model includes three objectives, the first objective seeks to minimize inter and intra-cell part movement, machine relocation, second objective minimize operator related cost, third objective maximize ratio of consecutive forward flows. The model is Multi-objective; therefore, the LP-metric approach is used to solve it. In order to validate the model, the proposed model has been solved by using Lingo software. Then, due to NP-hardness of the cell formation problem, for solving large scale problems, a multi-objective simulated annealing algorithm proposed. Several numerical examples solved by Lingo software and multi-objective simulated annealing algorithm. Results show that the proposed multi-objective simulated annealing algorithm solved considerably time less than the software Lingo and also none of ...

Facility location-allocation models are used in a widespread variety of applications to determine... more Facility location-allocation models are used in a widespread variety of applications to determine the number of required facility along with the relevant allocation process. In this paper, a new mathematical model for the capacitated multi-facility location-allocation problem with probabilistic customer's locations and fuzzy customer’s demands under the Hurwicz criterion is proposed. This model is formulated as α-cost minimization model according to different criteria. Since our problem is strictly Np-hard, a new hybrid intelligent algorithm is presented to solve the stochastic-fuzzy model. The proposed algorithm is based on a vibration damping optimization (VDO) algorithm which is combined with the simplex algorithm and fuzzy simulation (SFVDO). Finally, a numerical example is presented to illustrate the capability of the proposed solving methodologies.

International Journal of Procurement Management

Supplier selection and determination of order quantities with selected suppliers is one of the mo... more Supplier selection and determination of order quantities with selected suppliers is one of the most important activities in supply chain management. Hence, supplier selection problem should be performed by scientific methods and systematic approachs. In this study, a fuzzy multi objective model with an approach for supplier selection is presented. The fuzzy multi objective model with minimum and maximum order quantity constraint, delivery delay time constraint, defect number constraint and shortage number constraint is developed, then supplier selection problem solved by the extended model with fuzzy criteria weights that calculates by logarithmic least squares. In order to better description of the proposed approach and presented model, an example presented. Key-Words: Supplier selection, Fuzzy multi objective model, Logarithmic least squares approach.

Journal of Optimization in Industrial Engineering, 2020

In this research, a bi-objective model is developed to deal with a supply chain including multipl... more In this research, a bi-objective model is developed to deal with a supply chain including multiple suppliers, multiple manufacturers, and multiple customers, addressing a multi-site, multi-period, multi-product aggregate production planning (APP) problem. This bi-objective model aims to minimize the total cost of supply chain including inventory costs, manufacturing costs, work force costs, hiring, and firing costs, and maximize the minimum of suppliers' and producers' reliability by the considering probabilistic lead times, to improve the performance of the system and achieve a more reliable production plan. To solve the model in small sizes, a e-constraint method is used. A numerical example utilizing the real data from a paper and wood industry is designed and the model performance is assessed. With regard to the fact that the proposed bi-objective model is NP-Hard, for large-scale problems one multi-objective harmony search algorithm is used and its results are compared ...

Aggregate Production planning (APP) and preventive maintenance (PM) are most important issue carr... more Aggregate Production planning (APP) and preventive maintenance (PM) are most important issue carried out in manufacturing environments which seeks efficient planning, scheduling and coordination of all production activities that optimizes the company's objectives. In this paper, we develop two mixed integer linear programming (MILP) models for an integrated aggregate production planning system with return products, breakdowns and preventive maintenance. The goal is to minimize production breakdowns and Preventive maintenance costs and instabilities in the work force, inventory levels and downtimes, also effect of PM on the objective function. Additionally, Taguchi method is conducted to calibrate the parameter of the meta-heuristic and select the optimal levels of the algorithm’s performance influential factors. Due to NP-hard class of APP, we implement a harmony search (HS) algorithm for solving these models. Finally, computational results show that, the objective values obtain...

International Journal of Applied Operational Research - An Open Access Journal, 2014

Aggregate production planning (APP) is one of the most important issues carried out in manufactur... more Aggregate production planning (APP) is one of the most important issues carried out in manufacturing environments which seeks efficient planning, scheduling and coordination of all production activities that optimizes the company's objectives. In this paper, we develop a mixed integer linear programming (MILP) model for an integrated aggregate production planning system with closed loop supply chain and preventive maintenance. The goal is to minimize setup costs, production costs, labor costs and preventive maintenance (PM) costs and instabilities in the work force and inventory levels. Due to NP-hard class of APP, we implement genetic algorithm (GA), harmony search (HS) and vibration damping optimization (VDO) for solving this model. Additionally, the Taguchi method is conducted to calibrate the parameter of the meta-heuristics and select the optimal levels of the algorithm’s performance influential factors. Finally, computational results on a set of randomly generated instance...

 Abstract— This paper proposes a new mixed integer programming model for multi-item capacitated ... more  Abstract— This paper proposes a new mixed integer programming model for multi-item capacitated lot-sizing problem with setup times, safety stock and demand shortages in closed-loop supply chain the returned products from customers can either be disposed or be remanufactured to be sold as new ones again. The problem is NP-hard and to solve it, a simulated annulling approach is used. To verify and validate the efficiency of the SA algorithm, the results are compared with those of the Lingo 8 software. Results suggest that the SA algorithm have good ability of solving the problem, especially in the case of large and medium-sized problems for which Lingo 8 cannot produce solutions.

International journal of engineering. Transactions A: basics, 2007

This paper presents a novel, integer-linear programming (ILP) model for an identical parallel-mac... more This paper presents a novel, integer-linear programming (ILP) model for an identical parallel-machine scheduling problem with family setup times that minimizes the total weighted flow time (TWFT). Some researchers have addressed parallel-machine scheduling problems in the literature over the last three decades. However, the existing studies have been limited to the research of independent jobs, and most classical optimization methods are focused on parallel-machine scheduling problems without considering setup times and relationship between jobs. This problem is shown to be NP-hard one in the strong sense. Obtaining an optimal solution for this type of complex, large-sized problems in reasonable computational time is extremely difficult. A meta-heuristic method, based on genetic algorithms, is thus proposed and applied to the given problem in order to obtain a good and near-optimal solution, especially for large sizes. Further, the efficiency of the proposed algorithm, based on vari...

Journal of Optimization in Industrial Engineering, 2021

The supply chain network design not only assists organizations production process (e.g.,plan, con... more The supply chain network design not only assists organizations production process (e.g.,plan, control and execute a product’s flow) but also ensure what is the growing need for companies in a longterm. This paper develops a three-echelon supply chain network problem including multiple plants, multiple distributors, and multiple retailers with amulti-mode demand satisfaction policy inside of production planning and maintenance. The problem is formulated as a mixed-integer linear programming model. Because of its NP-hardness, three meta-heuristic algorithms(i.e., tabu search, harmony search and genetic algorithm) are used to solve the given problem. Also, theTaguchi method is used to choose the best levels of the parameters of the proposedmeta-heuristic algorithms. The results show that HS has abetter solution quality than two other algorithms.

Economic Computation and Economic Cybernetics Studies and Research, 2017

In this paper, we propose a Vibration Damping Optimization (VDO) algorithm with resonator loop as... more In this paper, we propose a Vibration Damping Optimization (VDO) algorithm with resonator loop as a meta-heuristic algorithm for solving resource constrained multi-project scheduling problem (RCMPSP). The objective is to determine the start time of the projects activities such that the total completion time of processes under the existing constraints would be minimized. This is the first attempt to develop a VDO algorithm for solving the RCMPSP. Also, a new solution representation scheme in a matrix form and special solution procedures are proposed. We explain the elements of the algorithm and solve some problems generated for this model including large size and small size instances. The performance of our proposed algorithm is evaluated by comparison with Simulated Annealing (SA) algorithm. The response surface methodology (RSM) is applied for tuning the parameters of the algorithms. The promising computational results validate the effectiveness of the proposed algorithm.

International Journal of Industrial Engineering & Production Research, 2017

This paper proposes a genetic algorithm (GA) to solve an integrated mathematical model for dynami... more This paper proposes a genetic algorithm (GA) to solve an integrated mathematical model for dynamic cellular manufacturing system (DCMS) and production planning (PP) concurrently. The model simultaneously seeks to determine the variables associated with the production planning and the cell construction and formation. The total costs include the cost of machine procurement, the cell reconfiguration cost, the cell setup cost, the unexpected variable costs of cells alongside the production planning costs. At first the mathematical model, which is an integer nonlinear programming (INLP), is converted to a linear programming (LP) model. Then, the branch and bound (B&B) method is used for solving small size problems employing the Lingo 8 software. Finally because the problem is NP- hard, a GA is used to solve the large-scale problems as a meta-heuristic algorithm. To evaluate the results obtained by the genetic algorithm, they are compared with those obtained with the Lingo 8 software. Com...

The main reason for the development of this research refers to the increased attention of busines... more The main reason for the development of this research refers to the increased attention of businesses to the CLSC concept due to the social responsibilities, strict international legislations and economic motives. Hence, this study investigates the issue of optimizing a CLSC problem involving multiple manufacturers, a hybrid cross-dock/collection center, multiple retailers and a disposal center in deterministic, multi-product and multi-period contexts. The bi-objective MILP model developed here is to simultaneously minimize total costs and total processing time of CLSC. Both strategic and tactical decisions are considered in the model where retailer demands and capacity constraints are satisfied. Since the presented model is NP-hard, NSGAII and MOPSO are hired to find near-to-optimal results for practical problem sizes in polynomial time.Then, to increase the accuracy of solutions by tuning the algorithms' parameters, the Taguchi method is applied. The practicality of the developed