考虑集结延误的列车编成辆数问题研究

货车集结是不可避免且耗时较长的技术作业环节，编成辆数与车辆集结延误时间密切相关.针对编成辆数问题，建立描述车辆在调车场集结过程的批到达批服务排队模型，分析车辆集结队长及延误时间等指标，并从经济角度求得最优最小编成辆数.结果表明，最优最小编成辆数受车组到达规律、车流到达强度和列车发车时间间隔影响.到达车组大小满足指数分布时，采用最优最小编成辆数策略节省经济效益优于几何分布和负二项分布；车流到达强度较小时，节省经济效益更显著；列车出发时间间隔分布满足几何分布时，效益优于负二项分布和均匀分布.

Number of Cars of a Departure Train Considering the Accumulation Delay

The accumulation is an inevitable and time-consuming railway technical operation, and the number of cars is closely related. A batch-arrival and batch-service queuing model for arrival-assembly-departure of cars was carried on using the method of queuing theory. Performance measures such as queue length and accumulation delays were discussed and then the optimal minimum number of cars considering economic efficiency was obtained. The numerical results show that the optimal minimum number of cars is related to car arriving pattern, arriving intensity and distributions of train departure schedules: (1) from the perspective of economic efficiency when adopting the optimal minimum number strategy, the case of arriving batch size satisfying exponential distribution is better than cases of geometric and negative binomial distributions; (2) when the arriving intensity is smaller, the economic efficiency is more remarkable; (3) the case of train departure schedules satisfying geometric distribution is better than cases of negative binomial and uniform distributions.