A goal programming mixed-model line balancing for processing time and physical workload

In this paper, we present a new mathematical model of line balancing for processing time and physical workload at the same time. Line balancing is the problem to assign tasks to stations while satisfying some managerial viewpoints. Most researches about the line balancing problems are focused on the conventional industrial measures that minimizing total processing time and/or number of workstations. Also, independently, some research reports insist some industrial ergonomic issues to be considered for balancing. So, we propose a zero-one integer program model that combines the overload of processing time and physical workload with various risk elements. For the solution techniques, we adopt the goal programming approach and design an appropriate algorithm process. Various computational test runs are performed on the processing time only model, the physical workload only model, and the integrated model. Comparing the pay-offs between the two overloads, test results show us that well balanced job allocation is able to be obtained through the proposed model. And we conclude that the model may be very useful for the operation managers to make decisions on their job scheduling efforts.