Cycle Time Reduction via Dynamic Job Shop Scheduling

Shi Jing

Abstract

Cycle time reduction plays an important role in improving the competitiveness and sustainability of a semiconductor manufacturer. However, in the past, cycle time reduction was usually unplanned owing to the lack of a systematic and quantitative procedure. To tackle this problem, a systematic procedure was established in this study for planning cycle time reduction actions to enhance the competitiveness and sustainability of a semiconductor manufacturing. Affected by the rapidly changing environment, online scheduling becomes a more and more critical challenge to most of the manufacturing industries. There are several researchers working on this area and plenty of methodologies had been proposed. However, there is no single methodology that can be used for all the problems due to the difference among the onsite situations. This study aims to improve the working efficiency of the production planning team by reducing the waiting time of the lots during queue in the line. Dynamic Job Shop Scheduling methodologies are applied and a multi-agent-based system is proposed. Simulation and experiments have been conducted to evaluate the new developed system. Data obtained from each of simulation experiments and existing system are compared by using statistics approaches. The result shows that the time that lots have to stay in waiting time could be decreased by almost 25% by applying this new scheduling system.