the problem of staff scheduling at a truck hub for loading and stripping of the trucks is an important and difficult problem to optimize the labor efficiency and cost. the trucks enter the hub at different hours a day, in different known time schedules and operating hours. in this paper, we propose a goal programming to maximize the labor efficiency via minimizing the allocation cost. the propo...

In this research, we develop a fuzzy multi-objective mathematical model to identify and rank the candidate suppliers and find the optimal number of new and refurbished parts and final products in a reverse logistics network configuration. This modeling approach captures the inherent uncertainty in customers’ demand, suppliers’ capacity, and percentage of returned products as well as existence o...

The aim of this paper is to develop an interactive two-phase method that can help the Project Manager (PM) with solving the fuzzy multi-objective decision problems. Therefore, in this paper, we first revisit the related papers and focus on how to develop an interactive two-phase method. Next, we establish to consider the imprecise nature of the data by fulfilling the possibilistic programming m...

The problem of solving a multi-objective programming problem, by assuming that the decision maker has fuzzy goals for each of the objectives, is addressed. In this case a fuzzy goal programming problem has to be solved. But when we have several objectives it can be a difficult task for the decision maker to determine coherent aspiration levels, so it is possible that the tolerance thresholds be...

Using the mathematic techniques such as Fuzzy approach has useful outcomes for production planning in different sources. In this paper LGP1 was used to model the objectives such as: avoidance of shortage or surplus of demand, access to maximum of income, using the normal capacity of production and organizing the inventory of warehouse, within the framework of Goal constraints like balancing b...