5.3.1	 Types	and	Benefits 52 5.3.2 Carbon Footprint and Life Cycle Assessment 53 5.3.3 Hazardous Substance Control 54 5.3.4 Light Rail Transit 54 5.4 Optimization of Customer Service 55 5.4.1 Service Performances 55 5.4.2 Customer Satisfaction 56 5.4.3 Customer Privacy 56 6.