Most existing human mobility literature focuses on exterior characteristics of movements but neglects activities. the driving force that underlies human movements. In this research. we combine activity-based analysis with a movement-based approach to model the intra-urban human mobility observed from about 15 million check-in records during a yearlong period in Shanghai. https://www.roneverhart.com/Pure-27-Blemish-Correcting-Purifying-Fluid/