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本文给出使用正交和连续小波变换(WT)以确定在综合的和实际的资料中的周期成倍和时间频率局地化。首先,将Haar小波分析应用于综合时间序列,由一简化的非线性动力系统一阶二次微分方程推导得出;第二,根据高分辨率日本静止卫星红外(IR)辐射资料,将复合Morlet小波用于研究热带对流的时间频率局地化。综合时间序列的Haar小波表明在一个周期成倍序列中多种频率的存在和明确的区分,周期成倍过程产生了中间频率的多重性,当振荡位相处于较低频率时,随时间的不均匀性可证明这一点,小波变换也能探测由周期成倍的分叉造成的高阶次谐波的极微弱的信号,由传统付氏分析看这些信号是不能测定,或被认为统计上无意义。红外辐射资料的Morlet小波变换表明在频率和时间二者上确定的多种时间尺度,红外资料分为湿期和干期二种状态,湿期有活跃的多种时间尺度,半日、日、几日及季内的尺度各有其结构,特别是在一个广泛的季内周期的湿位相中以天气尺度变化为主。这些不仅与以前用其它方法所发现的相一致,而且更为详尽,不同时间尺度间相互作用的振荡中的频率锁定关系指出,天气尺度的和季内变化都可以是混合振荡(由于热带大气及若干外力如太阳辐射的年或日变化等自我激发振荡造成的?
This paper presents the use of orthogonal and continuous wavelet transforms (WTs) to determine the period doubling and temporal frequency localization in the synthesized and actual data. First, Haar wavelet analysis is applied to the integrated time series, which is deduced from a simplified first order linear differential equation of nonlinear dynamical system. Secondly, based on the high resolution Japanese geostationary satellite infrared (IR) radiation data, the composite Morlet Wavelets are used to study the temporal frequency localization of tropical convection. The integrated time series Haar wavelet shows the existence and the definite distinction of multiple frequencies in a doubling sequence of one cycle. The multiplication of the intermediate frequency is caused by the cycle doubling process. When the oscillation phase is at a lower frequency, the variation over time It can be proved that wavelet transform can also detect very weak signals of higher-order harmonics caused by doubling cycles, which can not be measured or considered to be statistically insignificant by traditional Fourier analysis . Morlet wavelet transforms of infrared radiation data indicate various time scales determined on both frequency and time, with infrared data divided into wet and dry periods, active multiple time scales in wet periods, half day, day, few The scale of Japan and the South have their own structure, especially in the wet season in a wide range of seasonal cycles to weather-based changes. These are not only consistent with what was previously found by other methods, but more specifically, the frequency-locked relationship in oscillations of interaction between different time scales indicates that both synoptic and intraseasonal variations can be mixed oscillations (due to the tropical atmosphere and A number of external forces such as solar radiation or other changes in the self-excited oscillation caused?