A simulation-based DFSS for a lean service system

This paper describes a simulation-based approach for applying a lean Design for Six Sigma (DFSS) methodology on a service system. At the Identify stage, Quality Function Deployment (QFD) and Process Mapping are developed to assign Critical-to-Quality (CTQ) measures to the baseline of the service process. At the Design stage, Taguchi's P-Diagram and Discrete Event Simulation (DES) are utilised to incorporate process control and random factors into the stochastic and dynamic service process. At the Optimise stage, Design of Experiments (DOE) and Lean Techniques are applied to optimise process parameters and to enhance the structure of the service process so that Six Sigma performance and high process effectiveness are achieved. Finally, at the Verify stage, the DES model is used to verify the final process design in terms of robustness and economical viability. A case study of a dental clinic is used to clarify the application of the proposed approach.