3. Methods

The network of I-80 W is constructed by  SUMO and the dataset is collected from Open Street Map(OSM). The network has two input, which is the main highway stream and on-ramp,  and two output, I-80 W to San Francisco and I- 880 South and it shows on fig. \ref{270456} . PeMS( Caltrans Performance Measurement System ) dataset is used to find the flow on the highway and the station location is shown on  Fig. \ref{434937}.  Only weekday data is chosen and explore the entire April 2017 data.  The exploratory of PeMS data shows on Fig \ref{784815} .