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Global optimization method for mixed transportation network design problem: A mixed-integer linear programming approach 总被引:1,自引:0,他引:1
Paramet Luathep Agachai Sumalee William H.K. LamZhi-Chun Li Hong K. Lo 《Transportation Research Part B: Methodological》2011,45(5):808-827
This paper proposes a global optimization algorithm for solving a mixed (continuous/discrete) transportation network design problem (MNDP), which is generally expressed as a mathematical programming with equilibrium constraint (MPEC). The upper level of the MNDP aims to optimize the network performance via both expansion of existing links and addition of new candidate links, whereas the lower level is a traditional Wardrop user equilibrium (UE) problem. In this paper, we first formulate the UE condition as a variational inequality (VI) problem, which is defined from a finite number of extreme points of a link-flow feasible region. The MNDP is approximated as a piecewise-linear programming (P-LP) problem, which is then transformed into a mixed-integer linear programming (MILP) problem. A global optimization algorithm based on a cutting constraint method is developed for solving the MILP problem. Numerical examples are given to demonstrate the efficiency of the proposed method and to compare the results with alternative algorithms reported in the literature. 相似文献
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Traditionally, an assessment of transport network vulnerability is a computationally intensive operation. This article proposes
a sensitivity analysis-based approach to improve computational efficiency and allow for large-scale applications of road network
vulnerability analysis. Various vulnerability measures can be used with the proposed method. For illustrative purposes, this
article adopts the relative accessibility index (AI), which follows the Hansen integral index, as the network vulnerability
measure for evaluating the socio-economic effects of link (or road segment) capacity degradation or closure. Critical links
are ranked according to the differences in the AIs between normal and degraded networks. The proposed method only requires
a single computation of the network equilibrium problem. The proposed technique significantly reduces computational burden
and memory storage requirements compared with the traditional approach. The road networks of the Sioux Falls city and the
Bangkok metropolitan area are used to demonstrate the applicability and efficiency of the proposed method. Network manager(s)
or transport planner(s) can use this approach as a decision support tool for identifying critical links in road networks.
By improving these critical links or constructing new bypass roads (or parallel paths) to increase capacity redundancy, the
overall vulnerability of the networks can be reduced. 相似文献
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