一类Fork－Join排队系统的分析

本文研究了一类具有有限排队空间且其到达率和服务率均依赖于状态的Ｆｏｒｋ－Ｊｏｉｎ排队系统，给出了稳态概率和任务等待时间各阶矩的计算方法，并用仿真检验算法的正确性．     

基于成本的联络中心排队仿真与优化

传统的电话联络中心顾客等待时间长、容易放弃服务；排队人数过多，也会给联络中心造成一定的压力。因此考虑增加直接选择自动应答服务顾客排队的队列并重新分配坐席，以减少这一类顾客的排队时间。通过ProModel仿真实验，结果表明，新型排队模型成本和顾客放弃率有所降低，服务率得到提高，同时系统的阻塞率和服务人员繁忙率也有所降低，运行效果更好。     

一种通用的移动智能网SCF排队网络模型

在分析移动智能网SCF（Service Control Function）软件功能模型的基础上，提出了一种通用的SCF排队网络模型．然后以移动智能网中的预付费业务和短消息业务为例，使用具有反馈的M／G／1排队系统分析了业务消息的时延与消息到达率之间的关系，同时通过仿真对结果进行验证．仿真和分析结果的一致性表明，该排队网络模型是一个有效的数学模型，能用于快速地预测SCP（Service Control Point）系统的性能．     

排队规则为后进先出且系统容量有限的一类排队系统模型的计算机模拟

本文讨论了排队规则为后进先出，系统容量有限且服务时间与队长有关的一类排队系统机模型的计算机模拟，由于系统容量有限，当队长超过某一值时，到达系统的顾客将直接离开，不能进入系统接受任何服务，这将造成系统的某些损失，因此本文也讨论了影响系统信誉的损失率，在排队规则为后进先出和单服务台，串联及并联多服务台情形下建立六个模拟模型，这类模型在计算机系统，物资管理系统及情报系统中都有较广泛的使用，本文最后给出模     

考虑场桥效率的集卡失约优化仿真

码头外集卡预约系统能够有效的减少港口拥堵，提高港口作业效率，但是失约率是影响预约系统的重要因素。为研究失约对预约系统的影响，降低外集卡在闸口和堆场排队时间，建立考虑场桥资源配置的具有失约现像的集卡预约优化模型。模型利用马尔可夫和排队论分别计算外集卡在闸口和堆场的等待时间，应用matlab仿真，对模型进行深入探讨并给出详细的数值性能分析，同时量化了失约现象对预约系统损耗的影响，得出了不同失约率成本最低值。     

CICQ交换的流控实现机制和交叉点缓存容量分析

传统的基于crossbar的输入排队交换结构在提供良好的QOS方面存在很大的不足，而CICQ（combined input and crosspoint buffered queuing）交换结构与传统的交换结构相比，不但能在各种输入流下提供接近输出排队的吞吐率，而且能提供良好的QoS支持。文章分析了CICQ结构的流控实现机制，讨论了基于信用的流控机制的开销和实现方案，对crosspoint缓存容鼍作了分析，给出了在各种存储器写入条件下，保持交换结构100％吞吐率所需的最小缓存容量。     

容错磁盘阵列的性能模型

本文以排队论为工具，建立了容错磁盘阵列的Ｍ／Ｇ／１排队模型，并在此基础上分析了ＲＡＩＤ的平均响应时间，稳定数据传输率等重要性能指标；比较了同步和异步ＲＡＩＤ的性能差异，最后提出了以吞吐率作为衡量ＲＡＩＤ性能的综合指标，并给出了确定最大吞吐率的定量。     

排队网络在制造系统中的应用及其三维仿真实现

首先讨论了排队网络建模仿真工具的功能需求，提出了基于有向图的排队网络仿真建模机制，以及将面向对象与离散事件结合起来的仿真方法，根据排队网络的理论，结合图形建模方法和动画仿真技术的发展，研究了排队网络法的3D仿真实现，开发了一个面向制造系统和基于3D仿真的排队网络分析工具。     

一类具有随机离去策略的排队系统及其在Internet拥塞控制中的应用

当顾客到达一个排队系统时，可以根据当前队列的长度，按照一定的概率选择加入排队系统等待队列，或选择离开排队系统且不再返回。这样的排队系统称为“具有随机离去策略的排队系统”。我们利用输入流稀疏化（Thinning of recurrent flows）和输入流阻行（Balking）两种方法分别扩充了GI／M／1／N和GI^X／M／1／N两个排队系统，建立了3个具有随机离去策略的排队系统，给出了这类排队系统的顾客丢失率、系统利用率、队列长度的均值／方差、平均等待时间等性能指标。最后，讨论了这类排队系统在Internet拥塞控制中的应用。     

门限优先级系统的费用优化问题

在排队系统的设计或运营管理中,需要考虑顾客和服务双方的利益,以便在某种合理指标上使系统达到最优。陔文以此作为理论依据,建立了门限优先级系统的费用模型。运用排队理论建立的仿真模型对门限优先级系统的费用问题进行了量化分析。结果表明：随着服务率的增加,由于信元的逗留时间及丢失率减小,与之对应的排队损失费也随之减小,但同时服务费在增加;系统总费用有它的最小值,这时对应的服务率是最优值。这种分析方法在排队系统的设计中具有重要的参考价值。     

Using fluid models to prove stability of adversarial queueingnetworks

A digital communication network can be modeled as an adversarial queueing network. An adversarial queueing network is defined to be stable if the number of packets stags bounded over time. A central question is to determine which adversarial queueing networks are stable under every work-conserving packet routing policy. Our main result is that stability of an adversarial queueing network is implied by stability of an associated fluid queueing network     

Fuzzy service control of queueing systems

We consider queueing systems in which the service rate is the controlled variable. The cost depends on the queue length and selected rate. The objective is to choose the service rate dynamically, based on the state of the system so as to minimize the average cost over an infinite horizon. Six classes, either known in the literature or new, are studied in detail: queueing systems with vacations, single-server queueing systems with and without switching costs, and tandem queueing systems with and without service costs. A novel approach is presented here using fuzzy control to solve these problems. Simulation shows that the approach is efficient and promising, especially in cases where analytical solutions do not exist.     

Queueing Theory for Semiconductor Manufacturing Systems: A Survey and Open Problems

This paper surveys applications of queueing theory for semiconductor manufacturing systems (SMSs). Due to sophisticated tool specifications and process flows in semiconductor manufacturing, queueing models can be very complicated. Research efforts have been on the improvement of model assumptions and model input, mainly in the first moment (averages) and the second moment (variations). However, practices show that implementation of classical queueing theory in semiconductor industry has been unsatisfactory. In this paper, open problems on queueing modeling of SMS are discussed. A potential solution is also proposed by relaxing the independent assumptions in the classical queueing theory. Cycle time reduction has constantly been a key focus of semiconductor manufacturing. Compared with simulation, queueing theory-based analytical modeling is much faster in estimating manufacturing system performance and providing more insights for performance improvement. Therefore, queueing modeling attracts generous semiconductor research grants. Unfortunately, existing queueing models focus on simple extensions of the classical queueing theory and fail to question its applicability to the complicated SMS. Hence, related researches have not been employed widely in the semiconductor industry. In this paper, we conduct a survey on the important works and also present some open problems. We also propose a novel solution by relaxing a key assumption in the classical queueing theory. We are currently funded by Intel to explore this potential solution, and we hope it can foster an interesting research field for the years to come.     

General packet induced queueing schemes for reducing packet delays in ADSL routers with peer-to-peer file sharing applications

This paper proposes a class of queueing schemes named general packet induced queueing schemes (GPIQS) in ADSL routers to reduce the queueing delays of non-P2P packets. The objective of the proposed queueing schemes is to send out the general packets first as well as P2P packets are able to be sent in a bounded queueing delay. The proposed queueing schemes use the general packet to induce the transmission of P2P packets which are from the same client and arrived at the ADSL router before the general packet. The outbound order of the packets transmitted from a specific client is not altered in the proposed schemes. Two queueing schemes named general packet induced queueing scheme with single P2P queue (GPIQS-SQ) and general packet induced queueing scheme with multiple P2P queues (GPIQS-MQ) are proposed. The two proposed queueing schemes differ in the number of P2P queues. In order to prevent the unlimited waiting time of P2P packets, we introduced a variable called the largest number of preempting packets to send out the P2P packets in a bounded time. Simulation results show that the proposed queueing schemes may send out the packets from ADSL router efficiently and the average queueing delay is smaller than the common used first-come first-served algorithm. Specifically, the GPIQS-MQ performs better than the GPIQS-SQ method in terms of average queueing delay of non-P2P packets. We also found that the increased average queueing delay of P2P packets is small. Finally, the values of the largest number of preempting packets are discussed.     

A general solution for multichannel queueing systems with ordered entry

This paper presents a general solution of multichannel ordered entry queueing systems with heterogeneous servers and storage. It is assumed that the arrivals follow a Poisson distribution and the service times are exponentially distributed (M/M/n queueing system). A computer program was developed to solve this queueing system numerically. Measures of the system's performance as well as the steady-state probabilities are evaluated.     

Diffusion approximation and filtering for a queueing system with repeats

A single-channel Markov queueing system with repeats is considered. The number of waiting customers is shown to converge to an Ornstein-Uhlenbeck process. Filtering problems for this queueing system are considered.Translated from Kibernetika, No. 2, pp. 84–90, 104, March–April, 1990.     

Energy–delay tradeoff in a two-way relay with network coding

A queueing model for a relay in a communication network that is employing network coding is introduced. It is shown that communication networks with coding are closely related to queueing networks with positive and negative customers. The tradeoff between minimizing energy consumption and minimizing delay for a two-way relay is investigated. Analytical upper and lower bounds on the energy consumption and the delay are obtained using a Markov reward approach. Exact expressions are given for the minimum energy consumption and the minimum delay that are attainable.     

A finite waiting room queueing model with multiple servers having Markovian interruptions and its application to computer communications

A queueing model with finite waiting room, Poisson arrivals, multiple synchronous outputs and the number of active servers varying through the birth and death process is studied. Variation of active servers is obtained by providing a switch in each server. The switches are controlled through the birth and death process having finite population. The relationships between overflow probabilities, buffer size and expected queueing delay due to buffering are obtained. An efficient algorithm for computation of steady state probabilities is developed. Two digital voice-data systems; Data multiplexing in speech with synchronous Time Division Multiplexing (STDM) and Time Assignment Speech Interpolation (TASI) systems are considered for the application of the queueing model studied. The results of this study are portrayed on graphs and may be used as guidelines for designing a buffer in digital systems. The two voice-data systems using the developed model are simulated on the EC-1030 computer to check the validity of the analytical results. Although this problem arose in the study of data interpolation in STDM and TASI systems, the queueing model developed is quite general and may be useful for other industrial applications.