Papers by Hamed Kazemipoor
Journal of Mathematical and Computational Science, Jan 5, 2014
Recently, Kumar and Kaur (2011) proposed a new method, named as Mehar’s method, for solving fuzzy... more Recently, Kumar and Kaur (2011) proposed a new method, named as Mehar’s method, for solving fuzzy linear programming problem in which the element of coefficient matrix of the constrains are represented by real number and rest of the parameters are represented by fuzzy number, with converting to the classical linear programming problem. In this paper, we adopt this method for solving fully fuzzy linear programming problem (FFLPP) involving symmetric trapezoidal fuzzy numbers including both equality and inequality constraints. By using the proposed method the fuzzy optimal solution of FFLPP, occurring in real life situation, can be easily obtained. To illustrate the proposed method numerical examples are solved.
Journal of the Knowledge Economy
International Journal of Sustainable Energy
Sustainability
With the increase in pollutants, the need to use electric vehicles (EVs) in various urban logisti... more With the increase in pollutants, the need to use electric vehicles (EVs) in various urban logistics activities is an increasingly important issue. Currently, there are issues with the efficiency of transport companies in recognizing the effects of uncertain factors in daily logistics operations. Thus, this research proposes a novel fuzzy two-echelon vehicle routing problem involving heterogeneous fleet EVs and internal combustion vehicles (ICVs). The first echelon is recyclable wastes collected from waste pickup points and transported to the primary centers by EVs. The second echelon is transporting recyclable wastes to recycling centers by ICVs. In the proposed models, fuzzy numbers are used to express the rate and energy consumption depending on the amount of load, vehicle speed, and recyclable waste. In addition, a penalty cost of the time windows is considered in both echelons. The models are solved by CPLEX and two meta-heuristic algorithms, gray wolf optimizer (GWO) and tabu s...
Decision Making: Applications in Management and Engineering
In this paper, a stable CLSC problem is modeled in conditions of uncertainty and indeterminacy. T... more In this paper, a stable CLSC problem is modeled in conditions of uncertainty and indeterminacy. The SCN is designed to maximize NPV and minimize carbon releases by maintaining environment friendly policies and accounting for increase. To achieve a suitable model for designing a stable CLSCN and making important decisions such as selecting the right suppliers, selecting the type of transport, initial the facility, the optimal flow between facilities and accomplishing an efficient solution to the problem decision making, the neutrosophic optimization method is used. The results of experiments that discuss and evaluate different scenarios confirm the efficiency and validity of the proposed model. The findings also show that the effective improvement of the obtained solutions by reducing the solution time up to twenty percent can be responsible for large-scale problems in different scenarios. This paper uses a neutrosophic optimization method to solve the problem of designing a stable CLSCN under uncertainty and indeterminacy.
International Journal of Engineering, 2011
This paper presents a novel bi-objective manpower scheduling problem that minimizes the penalty i... more This paper presents a novel bi-objective manpower scheduling problem that minimizes the penalty incurred by the employees' assignment at lower skill levels than their real skills and maximizes the employees' utility by assigning them at desired skill levels in some shifts/days. Employees are classified in two specialist groups and three skill levels in each specialization. In addition, the presented model executes some essential work regulations. This paper also proposes a solution procedure based on the utility of objective values. Applying this procedure, an effective point is obtained for the given problem. This is the point where both objective functions have the highest utility simultaneously.
Expert Systems with Applications
Mudīriyyat-i ṣan̒atī, 2020
Objective: In this study, different ways of delivering goods to customers are created and therefo... more Objective: In this study, different ways of delivering goods to customers are created and therefore the vehicle routing decisions are added to this issue. In this case, customers must be divided into clusters and each customer assigned to one means of transportation in order to minimize the cost of orders between customers. In this study, the problem of integrated supply chain scheduling is determined by timely delivery of orders, scheduling orders on a machine in a manufacturing system and batch shipment, allocation to multiple heterogeneous transport modes according to capacity, and finally order delivery. To customers in the time window, it aims to minimize the total cost of distributing orders and the constant and variable costs of fuel and carbon emissions of the vehicle and the total time delay of customer orders. Methods: The problem programming model is a mathematical model of complex nonlinear integer and has been used for solving multi-objective meta-algorithms MOPSO and N...
International Journal of Research, 2020
Compatibility with the environment is one of the important factors in designing a supply chain sy... more Compatibility with the environment is one of the important factors in designing a supply chain system, which is also called the “green supply chain”. Similar to the supply chain, green suppliers are very important players in the green supply chain. This paper studies both selection of suppliers and optimal order allocation to them. Despite previous studies, we consider both strategic and operational decisions into the problem. Firstly, we investigate the relevant criteria in selecting suppliers, and assign appropriate weights to suppliers. Then, we apply the fuzzy TOPSIS technique to asses and rank the suppliers. Finally, we investigate optimal allocation of order to the suppliers. For this reason, a two-objective mathematical model is developed. To solve the model, “weighting” and “ɛ-constraint” methods will be investigated, followed by a sensibility analysis to study the changes in the problem’s parameters. The proposed approach is important because it models the strategic and ope...
International Journal of Innovation in Engineering, 2021
In this supply chain, blood and blood products are investigated as a product from donor to patien... more In this supply chain, blood and blood products are investigated as a product from donor to patient. Specific characteristics of blood supply chain such as perishability and existence of uncertainty in the structure of this chain have caused problems for planning in this regard. However, this point should be considered that the importance of this supply chain cannot be compared to perishable products. Life and death issue of this product is the main difference between blood and other perishable products. Therefore, a comprehensive model was presented in this study to locate blood bank components within a network and to determine the allocation of these components considering blood donation centers, blood testing and processing laboratories, distribution centers or blood banks, and demand centers. Since designing supply chain and locating issues at large dimensions are NP-hard, the suggested models at small sizes were compared using the exact method (GAMS), non-dominated genetic sorting algorithm, and multi-objective imperialist competitive algorithm. The results were compared with GAMS. This shows normal performance of the proposed algorithms and led to using these two algorithms at average and large sizes for research questions. Also, by analyzing sensitivity on important parameters, important managerial findings are suggested for similar conditions.
International Journal of Research, 2013
The fuzzy primal simplex method [15] and the fuzzy dual simplex method [17] have been proposed to... more The fuzzy primal simplex method [15] and the fuzzy dual simplex method [17] have been proposed to solve a kind of f uzzy linear programming (FLP) problems involving symmetric trap ezoidal fuzzy numbers. The fuzzy simplex method starts with a pri mal fuzzy basic feasible solution (FBFS) for FLP problem and moves to an optimal basis by walking truth sequence of exception of the optimal basis obtained in fuzzy primal simplex method don’t satis fy the optimality criteria for FLP problem. Also this method has no e fficient when a primal fuzzy basic FBFS is not at hand. The fuzzy d ual simplex method needs to an initial dual FBFS. Furthermore, th re exists a shortcoming in the fuzzy dual simplex method when t he dual feasibility or equivalently the primal optimality i s not at hand and in this case, the fuzzy dual simplex method can’t be u sed for solving FLP problem. In this paper, a fuzzy Big-M method is pro posed to solve these problems in which the primal FBFS is not read ily availabl...
Nowadays, Factories consider supply chain system as an essential tool for increasing competitive ... more Nowadays, Factories consider supply chain system as an essential tool for increasing competitive advantages. Under these certain conditions, creating proximity and long-term relationship between customers and suppliers can be taken into account as a vital factor in setting up the supply chain. Toward this regard, selecting the suppliers and logistics outsourcing have turned to the most important issue in creating this system. Human thoughts and judgment play a crucial role in determining the suppliers’ performance rate. Therefore, the fuzzy phenomenon will have more dominance on the systems distribution as long as the human force and complex systems are contributed in decision making. However, AHP method (Analytic Hierarchy Process) has more benefits over other approaches to evaluate the suppliers and logistics outsourcing. Using fuzzy AHP approach, we can minimize the deficiencies. This survey is aimed at prioritizing the suppliers and logistics outsourcing of a cement factory. Sis...
Journal of Industrial Engineering, International, 2010
Determining production rate considering costs and revenues in order to maximize profit is one of ... more Determining production rate considering costs and revenues in order to maximize profit is one of the applied problems in small and medium size factories. Mostly existing models in production planning consider production system statically and specify production rate, although the factors determining production rate include many different changes in practice. In fact, by increasing the production rate or mass production, production costs can be reduced. Costs reduction will result in sales price falling. Then, sales price will affect the demand and demand can increase. Demand increase will lead to more income and this process will repeat again. In this paper, a model will be proposed for production system of small and medium size companies regarding costs, revenues and dynamic reaction of systems against changes, by applying system dynamics and Vensim software. Since Iran is a developing country, the model will be analyzed and validated for a medium size factory and then some policies...
The use of an Electric Vehicle (EV), particularly in different operations of goods distribution i... more The use of an Electric Vehicle (EV), particularly in different operations of goods distribution is a solution for salvaging the crowded cities of the world from air and noise pollutions as well as Green House Gas (GHG) emission. This paper presents a Multi-Depot Electric Vehicle Routing Problem (MD-EVRP) with recharging stations by considering the expected penalty of fuzzy time windows in pickup/delivery. Since the MD-EVRP with Fuzzy Time Windows and Pickup/Delivery (MD-EVRP-FTW-PD) constraints is an NP-hard problem, three meta-heuristics (i.e., Simulated Annealing (SA), Variable Neighborhood Search (VNS) and a hybrid of SA and VNS (VNS-SA)) are used to solve such a hard problem. The parameters of these algorithms are measured by the Taguchi experimental design method. The proposed hybrid VNS-SA algorithm is more efficient in comparison with other algorithms.
International Journal of Innovation in Engineering, 2021
In this study, two mathematical models have been developed for assigning emergency vehicles, name... more In this study, two mathematical models have been developed for assigning emergency vehicles, namely ambulances, to geographical areas. The first model, which is based on the assignment problem, the ambulance transfer (moving ambulances) between locations has not been considered. As ambulance transfer can improve system efficiency by decreasing the response time as well as operational cost, we consider this in the second model, which is based on the transportation problem. Both models assume that the demand of all geographical locations must be met. The major contributions of this study are: ambulance transfer between locations, day split into several time slots, and demand distribution of the geographical zone. To the best of our knowledge the first two have not been studied before. These extensions allow us to have a more realistic model of the real-world operation. Although, in previous studies, maximizing coverage has been the main objective of the goal, here, minimizing operating costs is a function of the main objective, because we have assumed that the demand of all geographical areas must be met.
Ma at th he em ma at ti ic cs s & & I In nd du us st tr ri ia al l E En ng gi in ne ee er ri in n... more Ma at th he em ma at ti ic cs s & & I In nd du us st tr ri ia al l E En ng gi in ne ee er ri in ng g S Sp pe ec ci ia al l I Is ss su ue e
Journal of Facilities Management
Purpose The proposed model aims to consider the flying hours as a criterion to initiate maintenan... more Purpose The proposed model aims to consider the flying hours as a criterion to initiate maintenance operation. Based on this condition, aircraft must be checked before flying hours threshold is met. After receiving maintenance service, the model ignores previous flying hours and the aircraft can keep on flying until the threshold value is reached again. Moreover, the model considers aircraft age and efficiency to assign them to flights. Design/methodology/approach The aircraft maintenance routing problem (AMRP), as one of the most important problems in the aviation industry, determines the optimal route for each aircraft along with meeting maintenance requirements. This paper presents a bi-objective mixed-integer programming model for AMRP in which several criteria such as aircraft efficiency and ferrying flights are considered. Findings As the solution approaches, epsilon-constraint method and a non-dominated sorting genetic algorithm (NSGA-II), including a new initializing algorit...
Supply chain is one of the main pillars of manufacturing and industrial companies whose smartness... more Supply chain is one of the main pillars of manufacturing and industrial companies whose smartness can help business to be intelligent. To this end, the use of innovative technologies to make it smart is always a concern. The smart supply chain utilizes innovative tools to enhance quality, improve performance and facilitate the decision-making process. Internet of things (IoT) is one of the key components of the IT infrastructure for the development of smart supply chains that have high potential for creating sustainability in systems. Furthermore, IoT is one of the most important sources of big data generation. Big data and strategies for data analysis as a deep and powerful solution for optimizing decisions and increasing productivity are growing rapidly. For this reason, this paper attempts to examine informative supply chain development strategies by investigating the supply chain in FMCG industries as a special case and to provide a complete analytical framework for building a s...
Distributed generation (DG) will be an important part in the future power networks because of the... more Distributed generation (DG) will be an important part in the future power networks because of their potential for solving some of the problems related to mitigating line losses and improving system voltage profile. This paper presents a modified shuffled frog leaping algorithm (MSFLA) for allocating DGs for reducing losses and improves voltage profile of power networks. The objective function contains Voltage Profile Improvement Index (VPII) and Line Loss Reduction Index (LLRI) used in this paper in order to compute the line losses and voltage profiles. This study comprises a comparison between the MSFLA and SFLA methods implemented by MATLAB software on IEEE-34 bus radial distribution system. The simulations results revealed that MSFLA method can present better performance than the SFLA method.
Scheduling the supply chain in an integrated manner is a quite fundamental subject in supply chai... more Scheduling the supply chain in an integrated manner is a quite fundamental subject in supply chain management. To consider due-dates with production and distribution times at the same time could lead to reduced costs and, thereby, increased profitability. Integrating the problems dealing with due-date assignment, production/distribution times, and routing, while incorporating environmental considerations, could not only increase the cohesion among different decision-making levels and reduce costs in the long run, it would also contribute to the improvement of environmental conditions and benefit the world population. In this study, the integrated supply chain scheduling problem features assignment of due dates, batch delivery, assignment to multiple heterogeneous vehicles based on their capacity, and delivery of customer orders in time-windows. The objective is to minimize distribution cost, fixed and variable fuel costs, the carbon emitted by the vehicles, total delivery tardiness,...
Uploads
Papers by Hamed Kazemipoor