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21.
研究每个忙期中第一个顾客被拒绝服务的M/M/1排队模型的主算子在左半复平面中的特征值,证明对一切θ∈(0,1),(2√λμ-λ—μ)θ是该主算子的几何重数为1的特征值. 相似文献
22.
This paper develops a QKD (quantum key distribution)-based queueing
model to investigate the data delay on QKD link and network,
especially that based on trusted relays. It shows the mean
packet delay performance of the QKD system. Furthermore, it proposes a
key buffering policy which could effectively improve the delay
performance in practice. The results will be helpful for quality of
service in practical QKD systems. 相似文献
23.
Martin V. Day J. Hall J. Menendez D. Potter I. Rothstein 《Computational Optimization and Applications》2002,22(2):261-302
We generalize the analysis of J.A. Ball, M.V. Day, and P. Kachroo (Mathematics of Control, Signals, and Systems, vol. 12, pp. 307–345, 1999) to a fluid model of a single server re-entrant queue. The approach is to solve the Hamilton-Jacobi-Isaacs equation associated with optimal robust control of the system. The method of staged characteristics is generalized from Ball et al. (1999) to construct the solution explicitly. Formulas are developed allowing explicit calculations for the Skorokhod problem involved in the system equations. Such formulas are particularly important for numerical verification of conditions on the boundary of the nonnegative orthant. The optimal control (server) strategy is shown to be of linear-index type. Dai-type stability properties are discussed. A modification of the model in which new customers are allowed only at a specified entry queue is considered in 2 dimensions. The same optimal strategy is found in that case as well. 相似文献
24.
Consider a closed Jackson type network in which each queue has a single exponential server. Assume that N customers are moving among k queues. We establish simple closed form bounds on the network throughput (both lower and upper), which are sharper than those that are currently available. Numerical evaluation indicates that the improvements are significant. 相似文献
25.
In this paper, we develop an algorithmic method for the evaluation of the steady state probability vector of a special class of finite state Markov chains. For the class of Markov chains considered here, it is assumed that the matrix associated with the set of linear equations for the steady state probabilities possess a special structure, such that it can be rearranged and decomposed as a sum of two matrices, one lower triangular with nonzero diagonal elements, and the other an upper triangular matrix with only very few nonzero columns. Almost all Markov chain models of queueing systems with finite source and/or finite capacity and first-come-first-served or head of the line nonpreemptive priority service discipline belongs to this special class. 相似文献
26.
经济增长转型与就业促进 总被引:11,自引:0,他引:11
创造就业机会,解决失业问题,已经成为中国政府亟待解决的首要经济发展目标。本文深入分析了改革开放以来经济增长与就业增长之间、资本增长与就业增长之间、工资增长与就业增长之间的关系,并进一步深讨了经济转轨各个阶段就业模式的变化,以及正规就业与非正规就业对就业增长的影响。在此基础上,作者明确指出,经济增长与投资增长对扩大就业的作用正逐渐削弱,宏观经济政策与就业政策的改革也不足以彻底缓解就业压力,解决失业问题的关键在于实现经济增长模式从"经济增长优先"向"就业增长优先"型的转变,正确处理和协调劳动力密集型产业与资本密集型产业之间、劳工利益与资本利益之间、扩大内需与创造就业之间的关系。 相似文献
27.
We study multiclass queueing networks with the earliest-due-date, first-served (EDDFS) discipline. For these networks, the service priority of a customer is determined, upon its arrival in the network, by an assigned random due date. First-in-system, first-out queueing networks, where a customer's priority is given by its arrival time in the network, are a special case. Using fluid models, we show that EDDFS queueing networks, without preemption, are stable whenever the traffic intensity satisfies
j
<1 for each station j. 相似文献
28.
Ze-shui Xu 《佛山科学技术学院》2009,1(1):79-89
An intuitionistic preference relation is a powerful means to express decision makers’information of intuitionistic preference
over criteria in the process of multi-criteria decision making. In this paper, we first define the concept of its consistence
and give the equivalent interval fuzzy preference relation of it. Then we develop a method for estimating criteria weights
from it, and then extend the method to accommodate group decision making based on them And finally, we use some numerical
examples to illustrate the feasibility and validity of the developed method. 相似文献
29.
Winfried K. Grassmann Steve Drekic 《Methodology and Computing in Applied Probability》2008,10(1):73-83
A number of authors have recently suggested solving quasi birth-and-death (QBD) processes through the use of eigenvalue-based
methods. These methods take on a special form when there are multiple eigenvalues present. We investigate this problem in
a general setting as well as in the context of a specific preemptive priority queueing model.
相似文献
30.
A second-order fluid flow model of a queue with finite capacity buffer and variable net input process is presented, based
on the previous work of Karandikar and Kulkarni (1995). Queue length is modelled as a Brownian motion whose parameters are
controlled by a finite state Markov chain. The process, termed a Markov modulated regulated Brownian motion (MMRBM), provides
analytical solutions for steady state queue length distributions, overflow losses and idleness probabilities using boundary
regulators. Applications of the model include queues with failure-prone servers and ATM statistical multiplexers with variable
traffic loads.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献