Cost Modulus Research in Multi-Airport Ground-Holding Problem

According to the total coast of airlines and passengers, we define the cost unit as a function of the departure time of a aircraft in the multi-airport ground-holding model. This definition will reflect the GDP's cost degree more availably and emphasize the delay time's accumulative effect on all costs. By adjusting the value of parameters to suit the percentage of the cost factors, this modulus can apply to different kinds of applications.