We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponen...We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponential distributions.Whenever the server is available,it admits the retrial customers into service based on a first-come first-served rule.The service rate adjusts in real-time based on the retrial queue length.An iterative algorithm is proposed to numerically solve the personal optimal problem in the fully observable scenario.Furthermore,we investigate the impact of parameters on the social optimal threshold.The effectiveness of the results is illustrated by two examples.展开更多
Pooling,unpooling/specialization,and discretionary task completion are typical operational strategies in queueing systems that arise in healthcare,call centers,and online sales.These strategies may have advantages and...Pooling,unpooling/specialization,and discretionary task completion are typical operational strategies in queueing systems that arise in healthcare,call centers,and online sales.These strategies may have advantages and disadvantages in different operational environments.This paper uses the M/M/1 and M/M/2 queues to study the impact of pooling,specialization,and discretionary task completion on the average queue length.Closed-form solutions for the average M/M/2 queue length are derived.Computational examples illustrate how the average queue length changes with the strength of pooling,specialization,and discretionary task completion.Finally,several conjectures are made in the paper.展开更多
人类驾驶的不可控性使得间歇优先公交专用道(Bus Lanes with Intermittent Priority,BLIP)不能被有效利用。为解决该问题,本文提出智能网联车辆(Connected and Automated Vehicles,CAV)复用BLIP的控制方法。CAV借道控制考虑了公交车间...人类驾驶的不可控性使得间歇优先公交专用道(Bus Lanes with Intermittent Priority,BLIP)不能被有效利用。为解决该问题,本文提出智能网联车辆(Connected and Automated Vehicles,CAV)复用BLIP的控制方法。CAV借道控制考虑了公交车间移动区间的约束,还道控制考虑了与旁道CAV队列的协同,以应对还道安全距离不足的情况。并利用开放边界元胞自动机模型对提出的方法进行仿真。结果表明:同等流量下,CAV复用BLIP可大幅提高道路通行效率,且中等CAV渗透率下最显著,道路平均速度从6.67 km·h^(-1)提高至30.53 km·h^(-1);无论CAV渗透率高低,CAV队列协同换道都比单个CAV协同换道更有助于提高道路通行效率,相较之下将道路平均速度提高8%~19%。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.11971486)。
文摘We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponential distributions.Whenever the server is available,it admits the retrial customers into service based on a first-come first-served rule.The service rate adjusts in real-time based on the retrial queue length.An iterative algorithm is proposed to numerically solve the personal optimal problem in the fully observable scenario.Furthermore,we investigate the impact of parameters on the social optimal threshold.The effectiveness of the results is illustrated by two examples.
文摘Pooling,unpooling/specialization,and discretionary task completion are typical operational strategies in queueing systems that arise in healthcare,call centers,and online sales.These strategies may have advantages and disadvantages in different operational environments.This paper uses the M/M/1 and M/M/2 queues to study the impact of pooling,specialization,and discretionary task completion on the average queue length.Closed-form solutions for the average M/M/2 queue length are derived.Computational examples illustrate how the average queue length changes with the strength of pooling,specialization,and discretionary task completion.Finally,several conjectures are made in the paper.
文摘人类驾驶的不可控性使得间歇优先公交专用道(Bus Lanes with Intermittent Priority,BLIP)不能被有效利用。为解决该问题,本文提出智能网联车辆(Connected and Automated Vehicles,CAV)复用BLIP的控制方法。CAV借道控制考虑了公交车间移动区间的约束,还道控制考虑了与旁道CAV队列的协同,以应对还道安全距离不足的情况。并利用开放边界元胞自动机模型对提出的方法进行仿真。结果表明:同等流量下,CAV复用BLIP可大幅提高道路通行效率,且中等CAV渗透率下最显著,道路平均速度从6.67 km·h^(-1)提高至30.53 km·h^(-1);无论CAV渗透率高低,CAV队列协同换道都比单个CAV协同换道更有助于提高道路通行效率,相较之下将道路平均速度提高8%~19%。
