about the "w_time_ " parameter in KinodynamicAstar::estimateHeuristic()

[xiaozialei]

I want to ask about the intention for adding the "w_time_ " parameter in the KinodynamicAstar::estimateHeuristic().
In this function, the trajectory cost J(T) equals to -c1 / (3 * t * t * t) - c2 / (2 * t * t) - c3 / t + "w_time_" * t,
but in the paper "Robust and Efficient Quadrotor Trajectory
Generation for Fast Autonomous Flight,2019" the cost J(T) doesn't have the w_time_ parameter.

[CodenSxq]

I also want to why. Anyone could give me an answer?