Two-stage heuristics for single machine capacitated Iot-sizing and scheduling with sequence-dependent setup costs

This paper considers the single machine capacitated lot-sizing and scheduling problem (CLSP) with sequence-dependent setup costs. The problem is to determine the lot sizes and the sequence of lots while satisfying the demand requirements and the machine capacity in each period of a planning horizon. the setup state preservation, i.e., the setup state at the end of d period is carried over to the next period, is also considered. The objective is to minimize the sum of sequence-dependent setup and inventory holding costs over the planning horizon. Due to the complexity of the problem, wi suggest two-stage heuristics in which an initial solution is obtained and then it is improved using a backward and forward improvement method that incorporates various priority rules were done on randomly generated test instances and the results show that the two-stage heuristics outperform the best existing algorithm significantly