Before revision:  In order to capture the joint spatial-temporal dynamics of the intersections and road segments, we adopt the spatial-temporal learning layer that incorporates the multi-scale  spatial-temporal graph convolution networks and dual graphinteraction networks. Followed by the spatial-temporal learning layer, we also employ the multi-task learning layer to estimate the travel time of a given whole route and each road segment  simultaneously.
After revision:  In order to capture the joint spatial-temporal dynamics of the intersections and road segments, we adopt the spatial-temporal learning layer that incorporates the multi-scale spatial-temporal information from the dual graph. Finally, we employ the multi-task learning layer to estimate the travel time of a given whole route and each road segment simultaneously.