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EMD方法和Hilbert谱分析法的应用与探讨 被引量:124
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作者 熊学军 郭炳火 +1 位作者 胡筱敏 刘建军 《黄渤海海洋》 CSCD 北大核心 2002年第2期12-21,共10页
利用EMD方法对海浪观测资料进行处理 ,通过在数据两端的“平衡位置”处分别附加平行直线段的方法进行端点抑制 ,分解出 1 0个内在模函数和 1个剩余趋势项 ,再对各内在模函数进行Hilbert变换 ,得到波浪的Hilbert谱。对所得结果的分析表... 利用EMD方法对海浪观测资料进行处理 ,通过在数据两端的“平衡位置”处分别附加平行直线段的方法进行端点抑制 ,分解出 1 0个内在模函数和 1个剩余趋势项 ,再对各内在模函数进行Hilbert变换 ,得到波浪的Hilbert谱。对所得结果的分析表明 ,各模态在Hilbert谱中的分布趋势和Fourier谱中谱线的变化趋势是一致的 ,第一模态的中心频率与Fourier谱的谱峰频率相对应 ;EMD方法是对非线性、非平稳过程数据进行距平化的好方法 ,距平化的过程和消除趋势项的处理是统一的。 展开更多
关键词 EMD方法 海浪观测 端点抑制 Hilbert谱 距平化 经验模分解方法
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平流层大气臭氧含量变化特征
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作者 庞昕 庞伟 《河南气象》 2001年第4期27-28,共2页
利用卫星观测臭氧总含量TOMS(第7版)资料,分析了平流层臭氧含量的变化特征,结果表明,全球臭氧总含量呈下降趋势,准两年振荡是臭氧变化中除年周期外的最显著的变化周期。
关键词 臭氧 准两年变化 平流层 卫星观测 小波分析 距平化处理
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Impact of climatic change on sea surface temperature variation in Subei coastal waters,East China 被引量:2
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作者 王然 于非 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第6期1406-1413,共8页
Sea surface temperature (SST) variation in the Subei coastal waters, East China, which is important for the ecological environment of the Yellow Sea where Enteromorphaprolifera blooms frequently, is affected by the ... Sea surface temperature (SST) variation in the Subei coastal waters, East China, which is important for the ecological environment of the Yellow Sea where Enteromorphaprolifera blooms frequently, is affected by the East Asian winter monsoon (EAWM), El Nifio-Southem Oscillation (ENSO), and Pacific Decadal Oscillation (PDO). In this study, correlations between climatic events and SST anomalies (SSTA) around the Subei (North Jiangsu Province, East China) Coast from 1981-2012 are analyzed, using empirical orthogonal function (EOF) and correlation analyses. First, a key region was determined by EOF analysis to represent the Subei coastal waters. Then, coherency analyses were performed on this key region. According to the correlation analysis, the EAWM index has a positive correlation with the spring and summer SSTA of the key region. Furthermore, the Nifio3.4 index is negatively correlated with the spring and summer SSTA of the key region 1 year ahead, and the PDO has significant negative coherency with spring SSTA and negative coherency with summer SSTA in the key region 1 year ahead. Overall, PDO exhibits the most significant impact on SSTA of the key region. In the key region, all these factors are correlated more significantly with SSTA in spring than in summer. This suggests that outbreaks ofEnteromorpha prolifera in the Yellow Sea are affected by global climatic changes, especially the PDO. 展开更多
关键词 sea surface temperature (SST) Pacific Decadal Oscillation (PDO) El Nifio-Southem Oscillation(ENSO) East Asian winter monsoon (EAWM) Subei coastal waters
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Time-Dependent Nonlinear Forcing Singular Vector-Type Tendency Error of the Zebiak-Cane Model 被引量:1
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作者 ZHAO Peng DUAN Wan-Suo 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第5期395-399,共5页
Based on the Zebiak-Cane model, the timedependent nonlinear forcing singular vector (NFSV)-type tendency errors with components of 4 and 12 (denoted by NFSV-4 and NFSV-12) are calculated for predetermined El Nifio... Based on the Zebiak-Cane model, the timedependent nonlinear forcing singular vector (NFSV)-type tendency errors with components of 4 and 12 (denoted by NFSV-4 and NFSV-12) are calculated for predetermined El Nifio events and compared with the constant NFSV (denoted by NFSV-1) from their patterns and resultant prediction errors. Specifically, NFSV-1 has a zonal dipolar sea surface temperature anomaly (SSTA) pattern with negative anomalies in the equatorial eastern Pacific and positive anomalies in the equatorial central-western Pa- cific. Although the first few components in NFSV-4 and NFSV-12 present patterns similar to NFSV-1, they tend to extend their dipoles farther westward; meanwhile, the positive anomalies gradually cover much smaller regions with the lag times. In addition, the authors calculate the predic- tion errors caused by the three kinds of NFSVs, and the results indicate that the prediction error induced by NFSV-12 is the largest, followed by the NFSV-4. However, when compared with the prediction errors caused by random tendency errors, the NFSVs generate significantly larger prediction errors. It is therefore shown that the spatial structure of tendency errors is important for producing large prediction errors. Furthermore, in exploring the tendency errors that cause the largest prediction error for E1 Nifio events, the timedependent NFSV should be evaluated. 展开更多
关键词 PREDICTABILITY model error optimal perturbation
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A new record of Sebastes koreanus from China based on morphological characters and DNA barcoding 被引量:4
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作者 方亚璐 KAI Yoshiaki +2 位作者 YANAGIMOTO Takashi 宋娜 高天翔 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期590-596,共7页
A new record of Sebastes koreanus (Kim and Lee, 1994) was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Sample... A new record of Sebastes koreanus (Kim and Lee, 1994) was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study, specimens had the following morphological characteristics: light brown body with dark stripes and tiny dark spots, 4-5 wide indistinct vertical patterns on the side, 2 radial stripes behind and below the eyes, 1 large dark blotch on the opercle. Additionally, the following meristie characters were recorded: dorsal fin XIV-13, pectoral fin 16, anal fin III-6-7, pelvic fin [-5, lateral line scales 29-30, and vertebrae 26. The fragment of cytochrome oxidase subunit I (CO1) gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other Sebastes species ranged from 3.1% to 7.6%, which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion, evolution, patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research. 展开更多
关键词 Sebastes koreanus coastal waters of northern China new record morphological characters cytochrome oxidase subunit I (CO1)
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Co-integration Analysis of the Effect of Population Urbanization on Urban-rural Income Gap in Jiangxi Province
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作者 He Yinjuan 《International English Education Research》 2015年第6期19-21,共3页
This paper selects related data on the urbanization and the incomes of urban and rural residents in Jiangxi Province from 2000 to 2014, applies the theory of co-integration by Eviews Software, meanwhile, studies and a... This paper selects related data on the urbanization and the incomes of urban and rural residents in Jiangxi Province from 2000 to 2014, applies the theory of co-integration by Eviews Software, meanwhile, studies and analyzes the population urbanization and the income gap between urban and rural residents in Jiangxi Province through establishing an index system. Results: There is a cause-and-effect relationship, as well as duality, between the urban-rural income gap and the level of population urbanization in Jiangxi Province. With continuous promotion of the urbanization course in 1990-2014, the income gap between urban and rural residents in Jiangxi Province presents a phenomenon of expanding first, narrowing second and expanding again. 展开更多
关键词 Jiangxi Province URBANIZATION Income gap between urban and rural residents
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