考虑运营费用和线性化树形改编策略的货物列车开行方案研究

国外货物列车开行方案的制定通常以车流和车列的综合费用最小为目标，而我国大多以车流的集结和改编车小时消耗最小为目标，很少考虑每个车列的运营费用，造成理论开行费用偏小，其方案未必最优.此外，我国现有开行方案模型将车流树形改编策略递归表示，不利于对不可行流的处理.鉴于此，本文对现有模型进行改造，在总目标中增加车列运营费用；在约束中引入新的决策变量，实现线性化的车流树形改编策略.设计并行禁忌搜索算法实现对模型的求解.结果表明，单位列车运营费用中的固定费用对开行方案有着重要的影响，其费用越高，总开行列数越少，列车平均运距越长，但总改编车流量增加；线性化的改编策略直观展现车流的改编路径，便于对不可行流的运输方案进行调整.

Freight Train Service Design Problem with Operation Cost and Linearization Constraints for Carflow’s Tree-shaped Classification Strategy

With regard to formulating freight train operation plan, foreign countries generally take minimizing the integrated cost of traffic flow and train set as the objective. However, our country mainly focuses on minimizing the total train service accumulation cost and classification cost, rarely considering the operation cost of train set, which results that the theoretical operation cost is less than normal level and the operation plan may not be the best. Furthermore, the existing train formation plan models in our country recursively represent the traffic flow’s tree-shaped classification strategy, which is not conducive to deal with infeasible flow. In view of this situation, this paper modifies the existing models as follows: train set operation cost is added to the overall objective function and new decision variables are introduced into constraints to realize linearly representing the traffic flow’s tree-shaped classification strategy. Then, the parallel tabu search algorithm is designed to solve the proposed model. The results demonstrate that the fixed cost in unit train operation cost has a significant impact on train operation plan. The higher the fixed cost is, the smaller the total number of opening train is, the longer the average transport distance is, but the greater the total classification traffic flow is. Linearized classification strategy makes classification route of traffic flow much more intuitive so that it is easier to adjust the operation plan of infeasible traffic flow.