讲座主题： A Tollbooth Tandem Queue with Heterogeneous Servers
主讲嘉宾：何启明
讲座时间： 2017年3月1日（星期三）下午13:30—15:30
讲座地点：商学院116报告厅
欢迎感兴趣的老师和研究生们参加！
商学院
2017年2月26日
主讲嘉宾简介
何启明，加拿大滑铁卢大学管理科学系教授，加拿大运筹学会会员，INFORMS会员，主要从事运筹学（随机过程、排队论）及其应用方面的研究，在运筹学、管理科学领域Annals of Operations Research、Naval Research Logistics 、OMEGA: The International Journal of Management Science、Computer & Operations Research 、Performance Evaluation、Journal of Applied Probability、European Journal of Operational Research、Stochastic Models、J. of Asian-Pacific Journal of Operational Research等顶级期刊发表论文100余篇，并担任Annals of Operations Research、Performance Evaluation、Stochastic Models等多个期刊的编委。
讲座主要内容：
We study a tandem queueing system with K servers and no waiting space in between. A customer needs service from one server but can leave the system only if all down-stream servers are not occupied. Such a system is often observed in toll collection during rush hours in transportation networks, and we shall call it a tollbooth tandem queue. We apply matrix-analytic methods to study this queueing system, and obtain explicit results for various performance measures. Using these results, we can efficiently compute the mean and variance of the queue lengths, waiting time, sojourn time, and departure delays. Numerical examples are presented to gain insights into the performance and design of the tollbooth tandem queue. In particular, it reveals that the intuitive result of arranging servers in decreasing order of service speed (i.e., arrange faster servers at downstream stations) is not always optimal for minimizing the mean queue length or mean waiting time.
