中文摘要：

合理安排取送车顺序对提高机车劳动效率和加速车辆周转具有重要意义。针对树枝形专用线的直达车流取送问题，以车辆在装卸区总停留时间最小为目标函数，满足取送顺序间的逻辑关联约束，建立数学模型。结合后出线者先送、先完工者先取两条准则确定初始方案；引入送车代价和取车代价预先评估方案的有利性，设计隐枚举算法。算例表明：走行时间越离散或装卸时间越集中，寻优进程越缓慢；当专用线数目小于6时能迅速找到最优解，大于6时，设置合理的局部迭代阈值可较快地获得高质量解；获得多个满意解比单个耗费更多时间。

英文摘要：

Reasonable arrangement of taking-out and placing-in shunting operations are of great significance to raise locomotive productivity and speed up vehicle circulation . In this paper , the mathematical model for tak-ing-out and placing-in shunting of through wagon flow on branch-shaped sidings , was set up with minimizing its total residence time in the loading-unloading area as object function , and with the constraint of the logic cross relation between such two kinds of arrangements to be satisfied . The initial plan was determined accord-ing two criteria ,i.e. ,last departure first placing-in and first completion first taking-out . The implicit enu-meration algorithm was designed via assessing the plan′s profitability in advance , on the basis of introducing placing-in cost and taking-out cost scheme . Case study show s as follow s ：the more discrete the locomotive running time or the more intensive the loading-unloading operating time , the slower the optimization process . When the number of sidings is less than 6 , the best solutions can be rapidly found out . Otherwise , high quali-tative solutions can be obtained in short period by setting local iteration threshold . More compute time is spent in getting multiple satisfactory solutions than single one .