human resources scheduling based on machines maintenance planning and human reliability level

in today's competitive market, quality has an important role in manufacturing system. the manufacturers attempt to maintain their production system in a proper condition to produce high quality products. one of the key factors to achieve this goal is maintenance policy. most studies on maintenance focused on machines and less attention has been paid to human resources as the most important factor in manufacturing system. in this paper we propose a mixed integer nonlinear model to schedule the maintenance of machines and rest of human resources based on reliability factor. this model aims to minimize the cost of machines and human resources idleness and products quality cost. the performance of proposed model was examined by two instances and the obtained results indicated this model can provide efficient and effectiveness work and rest schedule for machines and human resources in manufacturing systems.