Integrated mixed-model assembly line balancing with unskilled temporary workers

Abstract

This study extends a single-model assembly line balancing problem to an integrated mixed-model assembly line balancing problem by incorporating unskilled temporary workers, who enhance productivity. An integer program that minimizes the sum of total workstation costs and salaries of skilled per-manent and unskilled temporary workers within a specific cycle time is devel-oped. The proposed models is based on particular features of a real-world problem including simultaneous assignments of skilled permanent and unskilled temporary workers as well as precedence restrictions for the tasks.