A bi-level decision support system for uncertain network design with equilibrium flow

a r t i c l e i n f o A bi-level decision support system (BDSS) is proposed for a normative road network design with uncertain travel demand. A bi-level decision support model with link capacity expansion is developed to simultaneously reduce travel delay to road users and mitigate vulnerability of road network. A tractable solution scheme for BDSS is developed. Due to some hierarchy in decision-making order of BDSS, a bi-level programming is employed. A risk-averse Stackelberg solution is established for a normative BDSS under travel demand uncertainty. Numerical computations are performed using a real-data road network. Computational results indicate that the proposed solution scheme can effectively improve a worst-case performance of BDSS with greater success while incurring a relatively slighter loss of optimality when compared to deterministic solutions at nominal condition. Particularly , our computation results showed that proposed solution becomes more attractive as the realization taken by unknown demand growth factor increases. For most urban traffic road networks, severe travel delays could be incurred by road travelers as a result of insufficient provision of link capacity in the presence of travel demand surges and disruptive events. In this paper, a bi-level decision support system (BDSS) is proposed to cope with continuously growing travel demand and alleviate increasing traffic congestion via link capacity expansion. For a road network with uncertain travel demand, decision maker at upper level determines link capacity expansion with an objective of minimizing total travel time constrained by investment budget. The road users at lower level are supposed to minimize their journey travel time [1] from pairs of origin to destination through route choice for realization taken by unknown travel demand which is most unfavorable. The solution for the decision maker with precedence in decision can be regarded as a Stackelberg solution. The Stackelberg solution is an optimal strategy for the leader when road users react by playing optimally. A worst-case analysis is considered for a normative BDSS in the presence of unknown travel demand to mitigate vulnerability of road network. In this regard, a bi-level model is proposed for BDSS in order to effectively characterize a risk-averse Stackelberg equilibrium at worst case scenario. In the presence of uncertainty there has been a growing number of research papers [2–8] investigating the performance reliability of networked system over past years. For instance, a spatial decision support system (SDSS) is developed in [5] to widely explore …