Some issues in network capacity reliability

As a commentary note, this paper attempts to elaborate and make constructive critiques on Chen et als paper in which four issues may be identified: (1) travelers rerouting behavior is not respected when degeneracy of link capacities occurs, (2) variations of link flows and capacities in time is not considered, (3) sensitivity information of network capacity with respect to link flow cannot be directly derived, and (4) the trial-and-error method used in solving the bi-level network reliability problem is computationally inefficient. A new reliability model formulation is thus proposed to resolve the first two shortcomings. The methodological framework of Chen et al is still adopted but with necessary modifications based in the last two comments. A numerical example is then provided to validate the proposed framework.