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11.
针对海量电信数据的聚类问题,利用粗集中的知识简化方法,减少属性的数量,提取主要的特征属性,并结合性能优良的模糊Kohonen聚类网络,提出了一种新的电信欺诈行为的检测模型,采用Microsoft SQL2005和VC++6.0技术,利用电信运营商提供的真实数据对该模型进行验证,实验结果表明,基于粗集神经网络方法提出的模型快速有效且具有较高的准确率。 相似文献
12.
Jean-François Monin 《Formal Methods in System Design》2000,17(3):221-243
Conformance control for ATM cells is based on a real-time reactive algorithm which delivers a value depending on inputs from the network. This value must always fit with a well defined theoretical value. We present here the correctness proof of the algorithm standardized for the ATM transfer capability called ABR. The proof turned out to produce a key argument during the standardization process of ABR. 相似文献
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This paper describes the design and implementation of an intelligent real-time supervision system for the monitoring and control of wastewater treatment plants. The system presents a hybrid structure which integrates knowledge engineering techniques and methodologies (an expert system based on production rules embodying non-mathematical or semiquantitative knowledge of unit operation) and algorithmic process-related methods (data acquisition, signal preprocessing, calculation of plant operation parameters etc.). The fundamental design aspects consist of temporal information treatment, artifact detection and a client- server structure which allows the telesupervision of various plants by a central system. 相似文献
14.
Taghi M. Khoshgoftaar Xiaojing Yuan Edward B. Allen 《Empirical Software Engineering》2000,5(4):313-330
Software product and process metrics can be useful predictorsof which modules are likely to have faults during operations.Developers and managers can use such predictions by softwarequality models to focus enhancement efforts before release.However, in practice, software quality modeling methods in theliterature may not produce a useful balance between the two kindsof misclassification rates, especially when there are few faultymodules.This paper presents a practical classificationrule in the context of classification tree models that allowsappropriate emphasis on each type of misclassification accordingto the needs of the project. This is especially important whenthe faulty modules are rare.An industrial case study using classification trees, illustrates the tradeoffs.The trees were built using the TREEDISC algorithm whichis a refinement of the CHAID algorithm. We examinedtwo releases of a very large telecommunications system, and builtmodels suited to two points in the development life cycle: theend of coding and the end of beta testing. Both trees had onlyfive significant predictors, out of 28 and 42 candidates, respectively.We interpreted the structure of the classification trees, andwe found the models had useful accuracy. 相似文献
15.
Marc St-Hilaire John W. Chinneck Steven Chamberland Samuel Pierre 《Computers & Industrial Engineering》2012
The 3G universal mobile telecommunications system (UMTS) planning problem is combinatorially explosive and difficult to solve optimally, though solution methods exist for its three main subproblems (cell, access network, and core network planning). We previously formulated the entire problem as a single integrated mixed-integer linear program (MIP) and showed that only small instances of this global planning problem can be solved to optimality by a commercial MIP solver within a reasonable amount of time ( St-Hilaire, Chamberland, & Pierre, 2006). Heuristic methods are needed for larger instances. This paper provides the first complete formulation for the heuristic sequential method ( St-Hilaire, Chamberland, & Pierre, 2005) that re-partitions the global formulation into the three conventional subproblems and solves them in sequence using a MIP solver. This greatly improves the solution time, but at the expense of solution quality. We also develop a new hybrid heuristic that uses the results of the sequential method to generate constraints that provide tighter bounds for the global planning problem with the goal of reaching the provable optimum solution much more quickly. We empirically evaluate the speed and solution accuracy of four solution methods: (i) the direct MIP solution of the global planning problem, (ii) a local search heuristic applied to the global planning problem, (iii) the sequential method and (iv) the new hybrid method. The results show that the sequential method provides very good results in a fraction of the time needed for the direct MIP solution of the global problem, and that optimum results can be provided by the hybrid heuristic in greatly reduced time. 相似文献
16.
电信牌照属于企业重要的无形资产,其内涵是由电信业务经营权、无线频段使用权和通信标准经营权组成的权利集合。在分析电信牌照资产获利能力及收益来源的基础上,综合采取净现值法和实物期权法对中国电信市场三张3G牌照的价值进行了评估测度。最后,基于测度结果围绕我国电信产业未来发展提出了政策建议。 相似文献
17.
本文分析了目前移动基站建设存在的主要问题及其产生根源,提出规范移动通信基站建设,将其作为城市公用设施纳入城市规划的观点.并根据国家及政府有关部门的政策法规及国内先行城市的成功经验,结合本市的实际情况,对规范移动通信基站建设的本地立法工作提出了建议. 相似文献
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近年来,我国自然灾害频发,灾害本身及次生灾害所带来的影响面非常广、国民经济和人民生命财产安全受到严重威胁,尤其是5.12汶川大地震,是对我国社会公共安全体系及社会公共保障能力的一次重大考验。国家应急通信保障作为国家专项应急保障的重要组成部分,在抗灾抢险、物资调运、灾情实时发布等方面起到了至关重要的作用。因此强化和完善通信网络应急保障体系,是当前乃至将来很长一段时间内的迫切要求。 相似文献