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591.
张忠君 《应用数学与计算数学学报》1999,13(1):85-90
对多级适应性休假的M/G/1排队系统,若休假时间服从位相型(PH)分布,我们证明了随机分解中的附加队长和附加延迟分别是离散和连续的PH随机变量,并给出其不可约PH表示,作为特例,国内外广泛研究的多重休假和单重休假系统,随机分解中的附加随机变量对PH分布都是封闭的。 相似文献
592.
The transient behavior of the finite-buffer queueing model with batch arrivals and generally distributed repeated vacations is analyzed. Such a system has potential applications in modeling the functioning of production systems, computer and telecommunication networks with energy saving mechanism based on cyclic monitoring the queue state (Internet of Things, wireless sensors networks, etc.). Identifying renewal moments in the evolution of the system and applying continuous total probability law, a system of Volterra-type integral equations for the time-dependent queue-size distribution, conditioned by the initial buffer state, is derived. A compact-form solution for the corresponding system written for Laplace transforms is obtained using an algebraic approach based on Korolyuk’s potential method. An illustrative numerical example presenting the impact of the service rate, arrival rate, initial buffer state and single vacation duration on the queue-size distribution is attached as well. 相似文献
593.
This paper considers a class of stationary batch-arrival, bulk-service queues with generalized vacations. The system consists of a single server and a waiting room of infinite capacity. Arrivals of customers follow a batch Markovian arrival process. The server is unavailable for occasional intervals of time called vacations, and when it is available, customers are served in groups of fixed size B. For this class of queues, we show that the vector probability generating function of the stationary queue length distribution is factored into two terms, one of which is the vector probability generating function of the conditional queue length distribution given that the server is on vacation. The special case of batch Poisson arrivals is carefully examined, and a new stochastic decomposition formula is derived for the stationary queue length distribution.AMS subject classification: 60K25, 90B22, 60K37 相似文献
594.
595.
A class of discrete-time closed cyclic networks is analyzed, where queues at each node have ample waiting room and have independent geometric service times with possibly unequal means. If each node has a single server or if there are sufficiently many parallel servers at each node to accommodate all jobs, equilibrium vectors of product form are obtained. For some other cases, equilibrium vectors of product form need not exist. For the single-server model, a normalization constant is computed and used to determine the queue-length distribution at a node. 相似文献
596.
This paper studies the operating characteristics of an M[x]/G/1 queueing system under a modified vacation policy, where the server leaves for a vacation as soon as the system is empty. The server takes at most J vacations repeatedly until at least one customer is found waiting in the queue when the server returns from a vacation. We derive the system size distribution at different points in time, as well as the waiting time distribution in the queue. Further, we derive some important characteristics including the expected length of the busy period and idle period. This shows that the results generalize those of the multiple vacation policy and the single vacation policy M[x]/G/1 queueing system. Finally, a cost model is developed to determine the optimum of J at a minimum cost. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
597.
598.
We propose a new methodology for modeling and analyzing power-tail distributions, such as the Pareto distribution, in communication
networks. The basis of our approach is a fitting algorithm which approximates a power-tail distribution by a hyperexponential
distribution. This algorithm possesses several key properties. First, the approximation can be achieved within any desired
degree of accuracy. Second, the fitted hyperexponential distribution depends only on a few parameters. Third, only a small
number of exponentials are required in order to obtain an accurate approximation over many time scales. Once equipped with
a fitted hyperexponential distribution, we have an integrated framework for analyzing queueing systems with power-tail distributions.
We consider the GI/G/1 queue with Pareto distributed service time and show how our approach allows to derive both quantitative
numerical results and asymptotic closed-form results. This derivation shows that classical teletraffic methods can be employed
for the analysis of power-tail distributions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
599.
双输人匹配排队系统是通常排队系统的一种推广.本文对该系统考察了L2-策略休假和服务台可修的两个重要因素.其中假定系统有两个不同的Poisson输入,两类顾客按1:1作成一批进行服务,服务台的寿命服从指数分布,服务时间,修理时间和休假时间都服从一般连续型分布,利用向量马氏过程方法,得到了该排队系统的一些重要的稳态排队论指标和可靠性指标. 相似文献
600.
在M/M/1排队中引入了不同的服务价格,基于"收益-成本"结构,以顾客和企业均追求利益最大化为出发点,在两种不可见情形下,研究了顾客均衡策略行为和企业最优服务定价决策,通过数值模拟,描述了休假期服务价格对顾客均衡策略的影响,以及几乎不可见情况下休假期服务价格对企业收益的作用和完全不可见情况下休假期服务价格随潜在到达率的变化情况,以及当企业获得最大收益时,正常工作期和休假期服务价格的关系. 相似文献