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31.
对新一代电信系统中业务管理机制进行研究。首先,指出了在新型业务开展中传统电信管理模式的不足。其次,分析了新一代电信管理系统中的信息组织形式,并分别从商务视点、商务流程以及商务价值三方面论述了业务管理在未来电信运营中的关键作用。最后,分析了业务管理中关键技术的研究现状,指出新一代业务管理未来的研究方向。  相似文献   
32.
数据在采集和传输过程中由于多种原因会造成矩阵残缺,因此在数据分析之前需要对残缺矩阵进行修复。常见的KNN修复方法 k值选取不合理,且需在整个矩阵中搜索近邻,影响算法的修复效果。在其基础上提出了一种k值自适应的局部KNN矩阵修复方法,合理考虑了k值的选取和近邻项的搜索范围。实验证明了该方法能有效提高矩阵修复的正确率,且算法的时效性有所提高。  相似文献   
33.
We address the probability that k or more Consecutive Customer Losses take place during a busy period of a queue, the so-called k-CCL probability, for oscillating GI X /M//n systems with state dependent services rates, also denoted as GI X /M(m)−M(m)//n systems, in which the service rates oscillate between two forms according to the evolution of the number of customers in the system. We derive an efficient algorithm to compute k-CCL probabilities in these systems starting with an arbitrary number of customers in the system that involves solving a linear system of equations. The results derived are illustrated for specific sets of parameters.  相似文献   
34.
We derive fast recursions to compute the probability that k or more consecutive customer losses take place during a busy period of a queue, the so called k-CCL probability, for regular and oscillating M X /G/1/n systems.  相似文献   
35.
The model of an open queueing network in heavy traffic has been developed. These models are mathematical models of computer networks in heavy traffic. A limit theorem has been presented for the virtual waiting time of a customer in heavy traffic in open queueing networks. Finally, we present an application of the theorem—a reliability model from computer network practice.  相似文献   
36.
《TOP》1986,1(1):127-138
Summary Many estimating procedures are carried out with incomplete data by means of different types of EM algorithms. They allow us to obtain maximum likelihood parameter estimates in classical inference and also estimates based on the posterior mode in Bayesian inference. This paper analyzes in detail the spectral radii of the Jacobian matrices algorithm as a possible way to evaluate convergence rates. The eigenvalues of such matrices are explicitly obtained in some cases and, in all of them, a geometric convergence rate is, at least, guaranteed near the optimum. Finally, a comparison between the leading eigenvalues of EM and direct and approximate EM-Bayes algorithms may suggest the efficiency of each case.  相似文献   
37.
The definition of quality in a ‘life’ environment, such as that of the World Wide Web has proven to have many, often conflicting interpretations. Factors such as the point of view, the expertise and type of usage of the critic can influence dramatically such a definition and its results. Thus, the key point is to distance oneself from single perspectives and obtain a complete picture of the system as a single entity working towards a specific goal. This paper is an attempt at creating a general model of quality procedures. It will concentrate mainly in customer service, system viability and quality of offering evaluation. Some of the material mentioned is based on adapted classical models that can be used equally to apply and observe standards of offerings in the wider WEB community. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
38.
本文在响应变量随机缺失时, 给出了广义半参数模型中响应变量的2个均值拟似然借补估计.证明了它们具有渐近正态性, 给出了估计的渐近偏差与渐近方差, 并进行模拟比较.  相似文献   
39.
本文在客户问卷调查的基础上,结合国外有关的物流企业客户服务指标,建立了物流客户服务水平评价的指标体系,同时应用定性与定量分析相结合的方法,建立了属性综合评价的物流客户服务水平评价模型,并给出了具体的应用实例.  相似文献   
40.
This paper analyzes data from experiments on simple polymer chains. It measures the extent to which a particular monomer prefers to link with another of the same type. To analyze the data, it derives the likelihood function for a two‐state Markov model in which only the number in each state, but not the order, is observed. This technology is applied to a data set on which experimenters mixed lactic‐glycolic monomers with a known proportion of a contaminant consisting of an extra lactic acid. The resulting copolymers were subjected to matrix‐assisted laser desorption ionization mass spectrometry. This records the number of copolymers at each atomic weight, which can be associated with a given length of copolymer and number of contaminant monomers. Analysis of the data shows that the proportion of contaminant monomers exceeded the proportion of experimentally induced contaminant. Maximum likelihood estimates using the data show that lactic‐glycolic monomers show a positive affinity for the contaminant. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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