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1.
一种新的WDM光网中的共享链路保护策略   总被引:2,自引:2,他引:0  
王云  曾庆济  刘继民 《光子学报》2003,32(7):798-802
研究了WDM光网中的链路保护问题.提出了一种新的共享链路保护策略--基于SRLG的共享链路保护策略(SRLG-SLP).SRLG(共享风险链路组)定义了对一条工作光通道分配保护资源时的资源可用性的约束.它规定任意两条有着同样故障风险或者说处于同一个SRLG的工作光通道不能利用同样的保护资源.另外,还提出了一种更加符合实际的单链路故障模型,其中链路故障间隔时间和链路故障保持时间被考虑作为两个独立的变量.基于该链路故障模型,通过大量的仿真试验,比较了专用链路保护(DLP)、共享链路保护(SLP)和提出的SRLG-SLP保护策略的资源利用率、保护效率以及业务中断率.结果显示,我们提出的SRLG-SLP在保护效率和业务中断率方面的保护性能远好于DLP和SLP,但会牺牲一些资源利用率.  相似文献   
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通过构建李雅普偌夫函数的方法和利用半鞅收敛定理对一类随机时滞神经网络的全局指数稳定进行了分析,提出了易于判定随机时滞神经网络几乎必然指数稳定性新的代数判据,推广了[1]中的主要结论.  相似文献   
4.
This paper develops a mathematical model for project time compression problems in CPM/PERT type networks. It is noted this formulation of the problem will be an adequate approximation for solving the time compression problem with any continuous and non-increasing time-cost curve. The kind of this model is Mixed Integer Linear Program (MILP) with zero-one variables, and the Benders' decomposition procedure for analyzing this model has been developed. Then this paper proposes a new approach based on the surrogating method for solving these problems. In addition, the required computer programs have been prepared by the author to execute the algorithm. An illustrative example solved by the new algorithm, and two methods are compared by several numerical examples. Computational experience with these data shows the superiority of the new approach.  相似文献   
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According to Fortunato and Barthélemy, modularity-based community detection algorithms have a resolution threshold such that small communities in a large network are invisible. Here we generalize their work and show that the q-state Potts community detection method introduced by Reichardt and Bornholdt also has a resolution threshold. The model contains a parameter by which this threshold can be tuned, but no a priori principle is known to select the proper value. Single global optimization criteria do not seem capable for detecting all communities if their size distribution is broad.  相似文献   
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We retrieve the radius R, real n and imaginary k parts of the refractive index of homogeneous spherical particles using angular distribution of the light-scattering intensity. To solve the inverse light-scattering problem we use a high-order neural-network technique. The effect of network parameters on optimization is examined. The technique is evaluated for noise-corrupted input data at 0.6 μm<R<10.6 μm, 1.02<n<1.38, and 0<k<0.03. The errors of retrieval for nonabsorbing particles do not exceed 0.05 μm for radius and 0.015 for refractive index. The experimental verification is fulfilled by experimental data retrieved by means of a scanning flow cytometer. The light-scattering profiles of polystyrene beads and spherized red blood cells are processed with the high-order neural networks and a non-linear regression at Mie theory. The parameters retrieved by the high-order neural networks correlate well with the parameters retrieved by the least-square method.  相似文献   
7.
神经网络在工程爆破应力波规律探讨中的应用   总被引:2,自引:0,他引:2  
采用BP(Back Propagation)前馈人工神经网络模型,对工程爆破中柱状震源的自由场应力波传播规律进行了探讨。结果表明:利用人神经网络模型的非线性映射功能,可以较好地给出工程爆破引起的近区自由场力学规律,对于同类型问题的研究,也有着很重要的意义。  相似文献   
8.
I.TntroductionStatisticalandneuralnetworkmcthodsforpatternclassiflcationusesignificantlydifTerentapproachesintrainingaclassificr.Inthestatistica1approach,thcformationofaclassifier1arge1ydependsonthestatisticsofthetrainingpatternsand,insomecases,theassumptionsaboutthedistributionofthepopulation.Theneuralnetworkmethodisnon-parametricandcanbeadaptivcinthetrainingprocessl'l.Becauseofitssimplicityandflexibility,theneuralnetworkhasbecnincreasing1yusedforpatternclassiflcation.Itisnowwe11knownthatan…  相似文献   
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In this paper, we analyze a discrete-time preemptive repeat priority queue with resampling. High-priority packets have preemptive repeat priority, and interrupted low-priority packets are subjected to independent retransmission attempts. Both classes contain packets with generally distributed transmission times. We show that the use of generating functions is beneficial for analyzing the system contents and packet delay of both classes. The influence of the priority scheduling on the performance measures is illustrated by some numerical examples. This work has been supported by the Interuniversity Attraction Poles Programme–Belgian Science Policy.  相似文献   
10.
Discrete-time GI/Geo/1 queue with multiple working vacations   总被引:2,自引:0,他引:2  
Consider the discrete time GI/Geo/1 queue with working vacations under EAS and LAS schemes. The server takes the original work at the lower rate rather than completely stopping during the vacation period. Using the matrix-geometric solution method, we obtain the steady-state distribution of the number of customers in the system and present the stochastic decomposition property of the queue length. Furthermore, we find and verify the closed property of conditional probability for negative binomial distributions. Using such property, we obtain the specific expression for the steady-state distribution of the waiting time and explain its two conditional stochastic decomposition structures. Finally, two special models are presented.   相似文献   
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