arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1104.0347math.PR
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顾客放弃的多服务台排队:扩散模型的数值分析

Many-server queues with customer abandonment: numerical analysis of their diffusion models

Shuangchi He, J. G. Dai

摘要:

我们使用多维扩散过程近似的动态队列由许多并行服务器。排队系统采用先进先出(FIFO)的服务顺序,排队等候的顾客可以在没有服务的情况下放弃系统。本文提出了两种扩散模型。它们的不同之处在于耐心时间分布是如何构建的。第一个扩散模型使用零的耐心时间密度,第二个使用整个耐心时间分布。为了分析这些扩散模型,我们开发了一个数值算法来计算这样一个扩散过程的平稳分布。该算法的一个关键部分是选择一个合适的参考密度。利用对有限队列长度过程尾部行为的一个猜想,我们提出了一个构造参考密度的系统方法。数值实验表明,该算法具有快速收敛性。这些实验还表明,扩散模型是很好的近似多服务器队列,有时只有20个服务器的队列。

英文摘要:

We use multidimensional diffusion processes to approximate the dynamics of a queue served by many parallel servers. The queue is served in the first-in-first-out (FIFO) order and the customers waiting in queue may abandon the system without service. Two diffusion models are proposed in this paper. They differ in how the patience time distribution is built into them. The first diffusion model uses the patience time density at zero and the second one uses the entire patience time distribution. To analyze these diffusion models, we develop a numerical algorithm for computing the stationary distribution of such a diffusion process. A crucial part of the algorithm is to choose an appropriate reference density. Using a conjecture on the tail behavior of a limit queue length process, we propose a systematic approach to constructing a reference density. With the proposed reference density, the algorithm is shown to converge quickly in numerical experiments. These experiments also show that the diffusion models are good approximations for many-server queues, sometimes for queues with as few as twenty servers.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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