Highway network (Hinton et al., 2012) has been shown to bring significant improvements to many NLP tasks, We apply a 4-layer highway network to u, and a single layer highway network is calculated as: where g is called as transform gate, (1 − g) is called as carry gate, and g = sigmod(W g u + b g ) .
the equivalent word embedding x c is finally worked out by a linear projection: x c is the equivalent word embedding calculated by CharCNN, which has the same dimension as x w obtained by looking up V e w ∈ R |V e w | * dw .