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基于熵权的年降雨量预报优化组合模型研究 被引量:2
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作者 王宝红 康永辉 +2 位作者 黄伟军 孙凯 解建仓 《安徽农业科学》 CAS 2014年第16期5142-5145,共4页
鉴于单一预测模型在建模时预测值比实际值存在较大偏差问题,为了提高预测精度,在此首先采用自回归综合移动平均ARIMA模型(简称A模型)、Elman神经网络模型(简称B模型)、小波网络分析模型(简称C模型)、灰色系统GM(1,1)模型(简称... 鉴于单一预测模型在建模时预测值比实际值存在较大偏差问题,为了提高预测精度,在此首先采用自回归综合移动平均ARIMA模型(简称A模型)、Elman神经网络模型(简称B模型)、小波网络分析模型(简称C模型)、灰色系统GM(1,1)模型(简称D模型),利用广西田东县1990~ 2007年的年降雨量分别进行了模拟计算,然后在各单一模型预测(拟合)的年降雨量偏差值基础上,应用熵权法对4种模型的偏差值进行客观赋权后优化组合,并根据最优组合结果,选用A、B、C单一模型和最优选的A-B-C优化组合模型对广西田东县2008~ 2010年的年降雨量进行预测对比.结果表明,A、B、C和A-B-C模型得到的均方根误差RMSE和模型效率EF分别为0.018、0.015、0.017、0.013和0.817、0.877、0.843、0.897,优化组合模型的预测精度和拟合度比单一模型的结果得到了提高和改善,该组合方法提高了年降水量的预测精度,为诸如广西田东县以雨养农业为主的区域农业干旱预报提供了新的方法和依据. 展开更多
关键词 ARIMA模型 ELMAN神经网络 小波网络分析 熵权 年降雨量 组合预测
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Wavelet neural network based fault diagnosis in nonlinear analog circuits 被引量:16
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作者 Yin Shirong Chen Guangju Xie Yongle 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期521-526,共6页
The theories of diagnosing nonlinear analog circuits by means of the transient response testing are studled. Wavelet analysis is made to extract the transient response signature of nonlinear circuits and compress the ... The theories of diagnosing nonlinear analog circuits by means of the transient response testing are studled. Wavelet analysis is made to extract the transient response signature of nonlinear circuits and compress the signature dada. The best wavelet function is selected based on the between-category total scatter of signature. The fault dictionary of nonlinear circuits is constructed based on improved back-propagation(BP) neural network. Experimental results demonstrate that the method proposed has high diagnostic sensitivity and fast fault identification and deducibility. 展开更多
关键词 fault diagnosis nonlinear analog circuits wavelet analysis neural networks.
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Improved wavelet neural network combined with particle swarm optimization algorithm and its application 被引量:1
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作者 李翔 杨尚东 +1 位作者 乞建勋 杨淑霞 《Journal of Central South University of Technology》 2006年第3期256-259,共4页
An improved wavelet neural network algorithm which combines with particle swarm optimization was proposed to avoid encountering the curse of dimensionality and overcome the shortage in the responding speed and learnin... An improved wavelet neural network algorithm which combines with particle swarm optimization was proposed to avoid encountering the curse of dimensionality and overcome the shortage in the responding speed and learning ability brought about by the traditional models. Based on the operational data provided by a regional power grid in the south of China, the method was used in the actual short term load forecasting. The results show that the average time cost of the proposed method in the experiment process is reduced by 12.2 s, and the precision of the proposed method is increased by 3.43% compared to the traditional wavelet network. Consequently, the improved wavelet neural network forecasting model is better than the traditional wavelet neural network forecasting model in both forecasting effect and network function. 展开更多
关键词 artificial neural network particle swarm optimization algorithm short-term load forecasting WAVELET curse of dimensionality
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