Congestion pricing is seen as an effective policy to address traffic congestion. In such policies where money, people and authorities are involved, the success generally hinges upon two factors： equity （being fair）...Congestion pricing is seen as an effective policy to address traffic congestion. In such policies where money, people and authorities are involved, the success generally hinges upon two factors： equity （being fair） and accept- ability （to both people and authorities）. The primary con- cern is the equity, for which ＂tradable credit scheme （TCS）＂ has been introduced and extensively studied in the literature. Nevertheless, due to the com- plexity of the trading schemes, the TCS has yet to find any foot in the real world. To this end, a novel idea of rewarding has substituted the trading component to be known as toll-and-subsidy scheme （TSS）. The idea is to charge the drivers on some roads （toll） while rewarding them to use other alternative--and perhaps underutilized-- roads （subsidy）. The research of the TSS is in its infancy stage. The problem to be tackled in this study is as follows： Given a set of roads constituting a cordon line around the central business district （CBD） or across a screen line, how much toll or subsidy should be assigned to each road？ The problem is first transformed into a capacitated traffic assignment problem. We employ a solution method based on augmenting the travel time of roads up to the level at which the traffic volumes do not exceed some target rates. A real dataset from the city of Winnipeg, Canada, is used as a pilot study. We then discuss policy-related applications of the TSS. It is proved in the literature that one can obtainoptimal TSSs for various objectives and considerations. To this end, the non-negativity of the toll values is relaxed which results in a valid toll set. Nevertheless, the compu- tational time is found to be of highest significance. Our method differs in the fact that the traffic volumes are bounded from the above and it is quite affordable. The main contribution is first to highlight the concept of sub- sidy along with traditional thought of merely toll. Second is to interpret the Lagrangian values of the capacity con- straints as the values of the toll/subsidy.展开更多
In order to address the optimal distance toll design problem for cordon-based congestion pricing incorporating the issue of equity,this paper presents a toll user equilibrium( TUE) model based on a transformed network...In order to address the optimal distance toll design problem for cordon-based congestion pricing incorporating the issue of equity,this paper presents a toll user equilibrium( TUE) model based on a transformed network with elastic demand,to evaluate any given toll charge function. A bi-level programming model is developed for determining the optimal toll levels,with the TUE being represented at the lower level.The upper level optimizes the total equity level over the transport network,represented by the Gini coefficient,where a constraint is imposed to the total travel impedance of each OD pair after the levy. A genetic algorithm( GA) is implemented to solve the bi-level model,which is verified by a numerical example.展开更多
文摘Congestion pricing is seen as an effective policy to address traffic congestion. In such policies where money, people and authorities are involved, the success generally hinges upon two factors： equity （being fair） and accept- ability （to both people and authorities）. The primary con- cern is the equity, for which ＂tradable credit scheme （TCS）＂ has been introduced and extensively studied in the literature. Nevertheless, due to the com- plexity of the trading schemes, the TCS has yet to find any foot in the real world. To this end, a novel idea of rewarding has substituted the trading component to be known as toll-and-subsidy scheme （TSS）. The idea is to charge the drivers on some roads （toll） while rewarding them to use other alternative--and perhaps underutilized-- roads （subsidy）. The research of the TSS is in its infancy stage. The problem to be tackled in this study is as follows： Given a set of roads constituting a cordon line around the central business district （CBD） or across a screen line, how much toll or subsidy should be assigned to each road？ The problem is first transformed into a capacitated traffic assignment problem. We employ a solution method based on augmenting the travel time of roads up to the level at which the traffic volumes do not exceed some target rates. A real dataset from the city of Winnipeg, Canada, is used as a pilot study. We then discuss policy-related applications of the TSS. It is proved in the literature that one can obtainoptimal TSSs for various objectives and considerations. To this end, the non-negativity of the toll values is relaxed which results in a valid toll set. Nevertheless, the compu- tational time is found to be of highest significance. Our method differs in the fact that the traffic volumes are bounded from the above and it is quite affordable. The main contribution is first to highlight the concept of sub- sidy along with traditional thought of merely toll. Second is to interpret the Lagrangian values of the capacity con- straints as the values of the toll/subsidy.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61374195 and 71501038)the Fundamental Research Funds for the Central Universities(Grant No.2242015R30036)the Natural Science Foundation of Jiangsu Province in China(Grant No.BK20150603)
文摘In order to address the optimal distance toll design problem for cordon-based congestion pricing incorporating the issue of equity,this paper presents a toll user equilibrium( TUE) model based on a transformed network with elastic demand,to evaluate any given toll charge function. A bi-level programming model is developed for determining the optimal toll levels,with the TUE being represented at the lower level.The upper level optimizes the total equity level over the transport network,represented by the Gini coefficient,where a constraint is imposed to the total travel impedance of each OD pair after the levy. A genetic algorithm( GA) is implemented to solve the bi-level model,which is verified by a numerical example.
