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Suspended sediment flux of river:Wavelet analysis in the Panlong basin of the Upper Red River (Honghe River),China

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Chinese Science Bulletin 2007年第A2期52卷 172-179页

作者： DING WenRong~(1,2+) ZHOU Yue~(1,3) L XiXi~4 1 The Faculty of Environment Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China 2 College of Tourism and Geography Science,Yunnan Normal University,Kunming 650092,China 3 Yunnan University of Finance and Economics,Kunming 650221,China 4 Department of Geography,National University of Singapore 119260,Singapore The Faculty of Environment Science and Engineering Kunming University of Science and Technology Kunming China College of Tourism and Geography Science Yunnan Normal University Kunming China Yunnan University of Finance and Economics Kunming China Department of Geography National University of Singapore Singapore

这份报纸把小浪分析用于检验变化趋势，多时间规模变化，在上面的红河的 Panlong 盆的推迟的沉积流动(SSF ) 的周期、突然的变化特征，中国。结果显示 SSF 从 1951 ～ 1997 增加了，但是自从 1998，衰退了。SSF 的变化把多时间规模特征... 详细信息

这份报纸把小浪分析用于检验变化趋势，多时间规模变化，在上面的红河的 Panlong 盆的推迟的沉积流动(SSF ) 的周期、突然的变化特征，中国。结果显示 SSF 从 1951 ～ 1997 增加了，但是自从 1998，衰退了。SSF 的变化把多时间规模特征和变化在不同时间时期改变了。三周期的时间规模， 4， 7 和 22 年，被决定。22 年的周期的时间规模，是在三次规模之中的最明显的，通过整个研究时期延长了，而第 4-a 7 年的时间规模在某些时间时期仅仅是明显的。分别地有 27 次越过 4 年的时间规模，越过 7 年的时间规模的 16 次和越过 22 年的时间规模的 5 次的突然的变化。根据统计的聚会和气候数据分析，我们断定人的活动是导致了多时间规模的 SSF，而是特征的变化趋势的主要原因，周期、突然的变化被气候变化主要影响。

关键词：河流中国红河微波分析

Analysis of the ionosphere wave-motion with GPS

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Chinese Science Bulletin 2005年第13期50卷 1373-1381页

作者： ZHANGHongping ZHUWenyao PENGJunhuan HUANGCheng ShanghaiAstronomicalObservatory ChineseAcademyofSciencesShanghai200030China//GraduateSchooloftheChineseAcademyofSciencesBeijing100039China ShanghaiAstronomicalObservatory ChineseAcademyofSciencesShanghai200030China//KeyLaboratoryofAdvancedEngineeringSurveyofSBSMTongjiUniversityShanghai200092China ShanghaiAstronomicalObservatory ChineseAcademyofSciencesShanghai200030China

Precise vertical total electron contents (VTEC) and its time variation have been obtained by using GPS dual-frequency observations collected by the continuously operating GPS tracking stations distributed over China. Us-ing VTEC data, the wave-motion appearing in the iono-sphere on November 3, 2003 is monitored and analyzed when a small solar flare happened. Detailed discussion with the VTEC and its change rate series, which are derived from the observations (data) from PRN23 satellite, indicates that the wave-motion mainly contains two dominant frequencies and propagates almost along the meridian line toward south. Additionally, the fluctuation of the mean VTEC has been calculated in a regional Single Layer Model (SLM) iono-spheric shell in the range of N28.0°―34.0° and E118.0°―123.0°. The spectral analysis and the multi-resolution analy-sis of mean VTEC time series show that the periods of these two components of the wave-motion at middle altitude are around 60 and 25 min separately, and the amplitudes can be up to 1.0―2.0 TECU and 0.4―0.7 TECU respectively. Mean- while, the relative motion between the wave-motion and the Ionosphere Pierce Points (IPPs), which are defined as the cross points between the line-of-sight of the GPS signals and the SLM thin shell, reveals that the traveling speeds of the two components are about 120―150 m/s and 30―40 m/s respectively.

关键词：电离波 GPS 全球定位系统光谱分析微波分析

A weak El Nino event in 2002 detected by the astronomical observation

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Chinese Science Bulletin 2003年第16期48卷 1709-1713页

作者： LIAODechun ZHOUYonghong LIAOXinhao ShanghaiAstronomicalObservatory ChineseAcademyofSciencesShanghai200030China NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012China UnitedCenterforAstro-GeodynamicsResearch ChineseAcademyofSciencesShanghai200030China

Using the length-of-day (LOD) data series de-rived from astronomical observations made by various mod-ern space techniques, southern oscillation index (SOI) and anomalies of sea surface temperature (SST) in tropical Pa-cific Ocean, the inter-annual components of these data series are obtained by the technique of band filtering from January 1962 to October 2002. It is found that a new ENSO event has already occurred in 2002 and been detected by the inter- annual LOD. It is shown by the wavelet analysis that the component with a period of about 46 years and the quasi-biennial component are out of phase during 2001 2002, which consequently suggests that the new ENSO event cannot be a strong one.

关键词：天文观测现代空间技术海洋表面温度太平洋微波分析厄尔尼诺现象海洋气候学

SOME PROPERTIES OF CENTROSYMMETRIC MATRICES AND ITS APPLICATIONS

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Numerical Mathematics A Journal of Chinese Universities(English Series) 2005年第2期14卷 136-148页

作者：刘仲云 College of Mathematics and Computing Science Changsha University of Science and Technology Changsha 410076 PRC.

In this paper, some properties of centrosymmetric matrices, which often appear in the construction of orthonormal wavelet basis in wavelet analysis, are investigated. As an application, an algorithm which is tightly related to a so-called Lawton matrix is presented. In this algorithm, about only half of memory units are required and quarter of computational cost is needed by exploiting the property of the Lawton matrix and using a compression technique, it is compared to one for the original Lawton matrix.

关键词：中心对称矩阵微波分析标准正交 Lawton矩阵