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基于最小二乘支持向量机的副热带高压预测模型 被引量:14
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作者 刘科峰 张韧 +2 位作者 洪梅 余丹丹 王辉赞 《应用气象学报》 CSCD 北大核心 2009年第3期354-359,共6页
采用EOF时空分解、小波频率分解和最小二乘支持向量机(LS-SVM)交叉互补方法,建立夏季500 hPa位势高度场的预测模型,用以描绘和表述副热带高压形势场的形态和变化。首先用经验正交函数分解(EOF)方法将NCEP/NCAR再分析资料500 hPa位势高... 采用EOF时空分解、小波频率分解和最小二乘支持向量机(LS-SVM)交叉互补方法,建立夏季500 hPa位势高度场的预测模型,用以描绘和表述副热带高压形势场的形态和变化。首先用经验正交函数分解(EOF)方法将NCEP/NCAR再分析资料500 hPa位势高度场序列分解为彼此正交的特征向量及其对应时间系数,随后提取前15个主要特征向量的时间系数(方差贡献96.2%),采用小波分解方法将其分解为相对简单的带通信号,再利用LS- SVM方法建立各分量信号的预测模型,最后通过小波时频分量重构和EOF时空重构,得到500 hPa位势高度场的预测结果以及副热带高压形势场的预测。通过对预测模型的试验情况和分析对比,结果表明:基于上述思想提出的算法模型能较为准确地描述500 hPa位势高度场的形态分布并预测1~7 d的副热带高压活动,对10~15 d的副热带高压活动预测结果也有参考意义。 展开更多
关键词 EOF分解 小波分解 遗传算法 支持向量机 副热带高压预测
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Relationship between Rice Planthopper Occurrence Area in China and Atmospheric Circulation Indices 被引量:3
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作者 季璐 朱敏 《Agricultural Science & Technology》 CAS 2012年第9期2006-2011,共6页
[Objective] This study aimed to establish models based on atmospheric cir- culation indices for forecasting the area attacked by rice planthopper every year, and to provide guide for preventing and controlling plantho... [Objective] This study aimed to establish models based on atmospheric cir- culation indices for forecasting the area attacked by rice planthopper every year, and to provide guide for preventing and controlling planthopper damage. [Method] The data related to rice planthopper occurrence and atmospheric circulation were collected and analyzed with the method of stepwise regression to establish the prediction models. [Result] The factors significantly related to the area attacked by rice plan-thopper were selected. Two types of prediction models were established. One was for Sogatella furcifera (Horvath), based on Atlantic-Europe circulation pattern W in October in that year, Pacific polar vortex area index in October in that year, North America subtropical high index in August in that year, Atlantic-Europe circulation pattern W in June in that year, northern boundary of North America subtropical high in February in that year, Atlantic-Europe polar vortex intensity index in October in that year and Asia polar vortex intensity index in November in the last year; the other type of prediction models were for Nilaparvata lugens (Stal), based on the Eastern Pacific subtropical high intensity index in July in that year, northern hemi- sphere polar vortex area index in October in the last year, Asia polar vortex strength index in November in the last year, north boundary of North America-At- lantic subtropical high in September in that year, north boundary of North Africa-At- lantic-North America subtropical high in January in that year, sunspot in September of the last year and eastern Pacific subtropical high area index in September in that year. [Conclusion] With the stepwise regression, the forecasting equations of the rice planthopper occurrence established based on the atmospheric circulation indices could be used for actual forecast. 展开更多
关键词 Rice planthopper Atmospheric circulation Prediction models
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Predicting Western Pacific Subtropical High Using a Combined Tropical Indian Ocean Sea Surface Temperature Forecast 被引量:2
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作者 WANG Li-Wei ZHENG Fei ZHU Jiang 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第6期405-409,共5页
Weather and climate in East China are closely related to the variability of the western Pacific subtropical high(WPSH), which is an important part of the Asian monsoon system. The WPSH prediction in spring and summer ... Weather and climate in East China are closely related to the variability of the western Pacific subtropical high(WPSH), which is an important part of the Asian monsoon system. The WPSH prediction in spring and summer is a critical component of rainfall forecasting during the summer flood season in China. Although many attempts have been made to predict WPSH variability, its predictability remains limited in practice due to the complexity of the WPSH evolution. Many studies have indicated that the sea surface temperature(SST) over the tropical Indian Ocean has a significant effect on WPSH variability. In this paper, a statistical model is developed to forecast the monthly variation in the WPSH during the spring and summer seasons on the basis of its relationship with SST over the tropical Indian Ocean. The forecasted SST over the tropical Indian Ocean is the predictor in this model, which differs significantly from other WPSH prediction methods. A 26-year independent hindcast experiment from 1983 to 2008 is conducted and validated in which the WPSH prediction driven by the combined forecasted SST is compared with that driven by the persisted SST. Results indicate that the skill score of the WPSH prediction driven by the combined forecasted SST is substantial. 展开更多
关键词 western Pacific subtropical high SST tropical Indian Ocean statistical prediction
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