南京信息工程大学学报
南京信息工程大學學報
남경신식공정대학학보
JOURNAL OF NANJING UNIVERSITY OF INFORMATION SCIENCE & TECHNOLOGY
2015年
3期
221-226
,共6页
雷暴预报%遗传算法%聚类分析%牛顿迭代法%小波神经网络
雷暴預報%遺傳算法%聚類分析%牛頓迭代法%小波神經網絡
뇌폭예보%유전산법%취류분석%우돈질대법%소파신경망락
thunderstorm forecasting%genetic algorithm%cluster analysis%Newton iteration method%wavelet neural network
为了进一步提高雷暴预报的准确率,在分析研究雷暴预报方法的基础上,提出了一种了基于改进遗传算法优化小波神经网络的雷暴预报方法( IGA?WNN)。该方法利用聚类分析和牛顿迭代法对多种群遗传算法的收敛方向和精度进行改进,避免了种群同质化与局部最优问题,采用改进的遗传算法对小波神经网络的初始权值阈值进行了优化。选用南京地区2008—2009年6—8月的探空和闪电定位资料,使用灰关联法挖掘出关联程度较大的对流参数作预报因子,归一化处理后输入模型,采用独立样本进行预报检验。结果表明,与 BP 神经网络等方法相比,IGA?WNN预报准确率更高,具有更好的非线性处理能力和泛化性。
為瞭進一步提高雷暴預報的準確率,在分析研究雷暴預報方法的基礎上,提齣瞭一種瞭基于改進遺傳算法優化小波神經網絡的雷暴預報方法( IGA?WNN)。該方法利用聚類分析和牛頓迭代法對多種群遺傳算法的收斂方嚮和精度進行改進,避免瞭種群同質化與跼部最優問題,採用改進的遺傳算法對小波神經網絡的初始權值閾值進行瞭優化。選用南京地區2008—2009年6—8月的探空和閃電定位資料,使用灰關聯法挖掘齣關聯程度較大的對流參數作預報因子,歸一化處理後輸入模型,採用獨立樣本進行預報檢驗。結果錶明,與 BP 神經網絡等方法相比,IGA?WNN預報準確率更高,具有更好的非線性處理能力和汎化性。
위료진일보제고뇌폭예보적준학솔,재분석연구뇌폭예보방법적기출상,제출료일충료기우개진유전산법우화소파신경망락적뇌폭예보방법( IGA?WNN)。해방법이용취류분석화우돈질대법대다충군유전산법적수렴방향화정도진행개진,피면료충군동질화여국부최우문제,채용개진적유전산법대소파신경망락적초시권치역치진행료우화。선용남경지구2008—2009년6—8월적탐공화섬전정위자료,사용회관련법알굴출관련정도교대적대류삼수작예보인자,귀일화처리후수입모형,채용독립양본진행예보검험。결과표명,여 BP 신경망락등방법상비,IGA?WNN예보준학솔경고,구유경호적비선성처리능력화범화성。
A thunderstorm forecasting method based on the Wavelet Neural Network optimized by the Improved Ge?netic Algorithm ( IGA?WNN) is put forward in order to improve the accuracy of thunderstorm potential prediction. This method takes use of Cluster Analysis and Newton Iteration Method to improve the convergence direction and precision of multiple population genetic algorithm,thus avoids population homogeneity and local optimum;and em?ploys improved Genetic Algorithm to optimize the initial weights of the threshold of wavelet neural network. The sounding data and lightning location data in Nanjing area from June to August during 2008 and 2009 were used for thunderstorm forecasting,and the convective parameters with higher degree of association,which were selected by grey correlation method,were normalized and put into the proposed model. Independent data are used to verify the forecast result.The forecasting and verification result indicate that,compared to other methods like BP neural net?work,IGA?WNN achieves higher prediction accuracy,and has better nonlinear processing capability as well as stron?ger generalization.