M.B. Aryanezhad - Industrial Engineering, Iran University of Science and Technology (IUST)
Seyed Amin Badri - Department of Industrial Engineering, University of Guilan

The goal of theory of constraints (TOC) is to maximize output, which is achieved byidentifying and managing the critically constrained resources. To manage the constraints, Goldrattproposed five focusing steps (۵FS). If we increase constrained output, the output of system will beincreased. In this paper, we focus on step four of the ۵FS and use the remained capacity of nonconstraintto elevate the system’s constraint.

theory of constraints, five focusing steps, Queueing system, Threshold