This paper designs a mathematical model for supply chain network design problem including plants, distributors and customers in fuzzy environment. Each plant and distributor has several levels capacities. A multi-mode demand strategy is considered for the customers where only one of the modes is to be selected for each customer. Considering the acceptance degree of fuzzy constraints violated, a...

This paper presents a new mathematical model for a bi-objective job shop scheduling problem with sequencedependent setup times that minimizes the weighted mean completion time and the weighted mean tardiness time. For solving this multi-objective model, we develop a fuzzy multi-objective linear programming (FMOLP) model. In this problem, a proposed FMOLP method is applied with respect to the ov...

In this paper we propose a multi-objective mathematical model to aid the marketing team of a company in customer service marketing. Customer reflects to the services provided by a company, and the reflections affect the profit of the company. Thus, the services can be evaluated by the customers to imply the company's performances. First, the services are purified based on the opinions of th...

In this paper, a hybrid meta-heuristic approach is proposed to optimize the mathematical model of a system with mixed repairable and non-repairable components. In this system, repairable and non-repairable components are connected in series. Redundant components and preventive maintenance strategies are applied for non-repairable and repairable components, respectively. The problem is formulate...

This paper formulates a mathematical model for the Green Vehicle Routing Problem (GVRP), incorporating bi-fuel (natural gas and gasoline) pickup trucks in a mixed vehicle fleet. The objective is to minimize overall costs relating to service (earliness and tardiness), transportation (fixed, variable and fuel), and carbon emissions. To reflect a real-world situation, the study considers: (1) a co...

With increasing competition in the business world and the emergence and development of new technologies, many companies have turned to integrated production and distribution for timely production and delivery at the lowest cost of production and distribution and with the least delay in delivery. By increasing human population and the increase in greenhouse gas emissions and industrial waste, in...

One of the most comprehensive theories stochastic models is queueing theory. Through innovative analytical research with broad applicability, advanced theoretical are being developed. In present research, we would like to investigate at a queuing network model low and high priority users different server transition probabilities. The two service channels used in this study, <img src=image/13428...

Local Container Drayage Problem (LCDP) refers to the optimization of process planning and scheduling container trucks between a terminal customers offer door-to-door service in local area. The time required for (un)packing containers at customers’ sites are often relatively long uncertain due current work level unexpected deviations operational situations, which has significant influence on tra...