Optimal resource allocation for hybrid flow shop in one-of-a-kind production

In one-of-a-kind production (OKP) companies, the number of production resources in each work centre of a production line is flexible in shifts because the resource demands of customer orders are always different from shift to shift. In this paper an optimisation model is established to achieve an optimal resource allocation plan ensuring that all jobs are finished in a given time interval with a minimum number of resources and without any buffer overflow. A branch-and-bound algorithm is developed to solve the problem. Two theorems are proved and applied in the algorithm to improve its pruning efficiency. A real industrial application is implemented for Gienow Windows and Doors Ltd. based on this model and algorithm. Experimental results show that this method is effective.