Integrated modelling of loT production scheduling and machines maintenance scheduling for multiple items processed on two series deteriorating machines in JIT environment

This paper develops an integrated modelling of lots production scheduling and machines maintenance scheduling on flow shop with two machines. The manufacturing system produces multiple items to be delivered at a common due date. This model describes a trade-off between lot production cost and machines maintenance cost as number and quantity of lots on the series machines. The objective function of the integrated model is total cost minimization that is consisting of in process inventory lots and completed lots inventory cost, machines setup costs, preventive maintenance cost, corrective maintenance cost and rework cost on two series deteriorating machines. The step wise optimization algorithm developed to solve the mixed integer quadratic programming of the problem model. Comparison with the practice and the model sensitivity analysis are showed to clarify how the algorithm works.