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YE Jia jun CHEN Jian QIAN Ying TIAN Yang lin 《上海大学学报(英文版)》1999,3(3):214-217
1 Introduction TheOFDMtechnologyiswidelyusedinthemodernhighspeeddatacommunicationapplications,suchasthedigitalbroadcastingsystemincludingDVB(thedigitalvideobroadcasting)andDAB(thedigitalaudiobroadcasting),thebroadbandaccessnetworkincludingADSL(theas… 相似文献
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A卷 1.在所给单词中找出划线部分读音不同的词(5分) ()1.A.place B.safe C.wake D.have ()2.A.she B.these C.letter D.metre ()3. A. wide B, nice C. live D. white ()4.A.dog B,those C.shop D.forgot ()5.A.excuse B.number C.student D.Tuesday ()6.A.farm B.hard C.warm D.card ()7.A.whose B.whole C.wh… 相似文献
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ARandomMultiAccessMethodforDataServicesinCDMACelularSystemLiZhen(李振)YouXiaohu(尤肖虎)(NationalMobileCommunicationsResearchLabor... 相似文献
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M.Tahir Khaleeq Lang Wengpeng He Guoseng 《上海大学学报(英文版)》1998,2(2):127-134
NomenclatureAArea(m2)DhHydraulicDiameter(m)EEnergyContent(J)fPressureLossCoeficientαVoidFractionHSpecificEnthalpy(J/kg)IInert... 相似文献
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一、语音知识(共8小题 ;每题1.5分 ,共12分)在下列每组单词中 ,有一个单词的划线部分与其他单词的划线部分的读音不同。找出这个单词。1.()A.measureB.pleasureC.usually D.sugar2.()A.quarrelB.dangerousC.congratulationD.operate3.()A.satelliteB.secretaryC.severalD.sentence4.()A.stomachB.otherwiseC.wonderD.continent5.()A.f… 相似文献
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INTRODUCTIONInexcavation ,normalanalysisisnotgoodenoughtomeetengineeringneedsduetotheun certaintyofforcesappliedonbracestructures,soilcharacteristics,andsoilmodelused .Toguaranteethattheconstructionprocesscanbesmoothlyperformed ,measurementsinsituareusua… 相似文献
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对BP型ANN网络用于模拟电路故障诊断的特点进行了介绍,探讨了利用遗传算法确定BP型ANN网络参数的方法,并给出了遗传算法与BP型ANN相结合实现模拟电路故障诊断的应用.实践表明,该方法的诊断精度、诊断速度以及建立诊断模型的自动化程度都有了较大的提高. 相似文献
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Electrical discharge machining (EDM) process, at present is still an experience process, wherein selected parameters are often far from the optimum, and at the same time selecting optimization parameters is costly and time consuming. In this paper, artificial neural network (ANN) and genetic algorithm (GA) are used together to establish the parameter optimization model. An ANN model which adapts Levenberg-Marquardt algorithm has been set up to represent the relationship between material removal rate (MRR) and input parameters, and GA is used to optimize parameters, so that optimization results are obtained. The model is shown to be effective, and MRR is improved using optimized machining parameters. 相似文献
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Parameters optimization and nonlinearity analysis of grating eddy current displacement sensor using neural network and genetic algorithm 总被引:1,自引:0,他引:1
A grating eddy current displacement sensor (GECDS) can be used in a watertight electronic transducer to realize long range displacement or position measurement with high accuracy in difficult industry conditions. The parameters optimization of the sensor is essential for economic and efficient production. This paper proposes a method to combine an artificial neural network (ANN) and a genetic algorithm (GA) for the sensor parameters optimization. A neural network model is developed to map the complex relationship between design parameters and the nonlinearity error of the GECDS, and then a GA is used in the optimization process to determine the design parameter values, resulting in a desired minimal nonlinearity error of about 0.11%. The calculated nonlinearity error is 0.25%. These results show that the proposed method performs well for the parameters optimization of the GECDS. 相似文献
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Xu Ri-qing 《浙江大学学报(A卷英文版)》2000,1(4):408-413
This paper presents a new method (GA-ANN) developed by combining genetic algorithm (GA) and artificial neural networks (ANN)
for determining parameters of soils and retaining walls of deep excavation. This method has the advantages of nonlinear projection
of neural networks, networks reasoning, prediction and good overall characteristics. it was first used for back analysis of
the problem of mechanics parameters for excavation. Case studies showed that the GA-ANN method is effective and practical
for back analysis of determining parameters.
Project supported by NSFC(5973860) and National Civil Defence fund of China 相似文献
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This paper deals with a multi-objective parameter optimization framework for energy saving in injection molding process. It
combines an experimental design by Taguchi’s method, a process analysis by analysis of variance (ANOVA), a process modeling
algorithm by artificial neural network (ANN), and a multi-objective parameter optimization algorithm by genetic algorithm
(GA)-based lexicographic method. Local and global Pareto analyses show the trade-off between product quality and energy consumption.
The implementation of the proposed framework can reduce the energy consumption significantly in laboratory scale tests, and
at the same time, the product quality can meet the pre-determined requirements. 相似文献
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Regression-Based Artificial Neural Network Methodology In Response Surface Methodology 总被引:3,自引:0,他引:3
Response surface methodology (RSM) is an important tool for process parameter optimization, robust design and other quality improvement efforts. When the relationship between influential input variables and output response is very complex, it‘ s hard to find the real response surface using RSM. In recent years artificial neural network (ANN) has been used in RSM. But the classical ANN does not work well under the constraints of real applications. An algorithm of regression-based ANN(R-ANN) is proposed in this paper, which is a supplement to the classical ANN methodology. It makes network closer to the response surface, so that training time is reduced and robustness is strengthened. The procedure of improving ANN by regressions is described and the comparisons among R-ANN, RSM and classical ANN are computed graphically in three examples. Our research shows that the R-ANN methodology is a good supplement to the RSM and classical ANN methodology, which can yield lower standard error of prediction under conditions that the scope of experiment is rigidly restricted. 相似文献
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周晓海 《河北职业技术学院学报》2009,(2)
介绍了人工神经网络的生理基础以及算法的基本结构,对其在水文地质学中进行反求参数的应用进行了阐述,并就应用的具体步骤及所建立的网络模型进行讨论。 相似文献
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周晓海 《廊坊师范学院学报(自然科学版)》2009,9(2):43-44,47
介绍了人工神经网络的生理基础以及算法的基本结构,对其在水文地质学中进行反求参数的应用进行了阐述,并就应用的具体步骤及所建立的网络模型进行讨论。 相似文献
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应用人工神经网络(Artificial Neural Network,ANN)算法对MIT-BIH心电数据库中的数据进行检测,对波形辨识算法做初步研究。设计三层神经网络结构:输入层、隐含层和输出层。从心电信号中提取4项特征参数作为输入层的输入量,并对MIT-BIH心电数据库中的15例心电数据进行了检测。表明该算法对QRS波总体检测灵敏度为98.96%,检测真阳性率为99.93%,对室性异位博动检测灵敏度为94.97%,检测真阳性率为98.72%。实验证实该神经几乎络算法对心电波形辨识非常有效。 相似文献