“…Production cycle time for each layer is different due to the difference in machine units, utilization rates, and operation times of the workstation type specified in a product's process plan. The ratio of production cycle time to theoretical processing time of a product is called X-factor, which is usually used as a reference for production progress control (Kishimoto, Ozawa, Watanabe, & Martin, 2001). Therefore, based on X-factor and theoretical processing time of a layer, layer cycle time for a product can be estimated.…”