VARIATIONAL ITERATION SOLVING METHOD FOR SEA-AIR OSCILLATOR MODEL OF INTERDECADAL CLIMATE FLUCTUATIONS

1IN T R O D U C T IO NInteractionsbetween the ocean and atmosphere con-tributeto climatefluctuationosver a broad spectrum oftime scales.Studiesof those interactionhsave farfo-cused on El Ni o-SouthernOscillation(ENSO)phe-nomenon thathas a period of3to4yea…     

地震通信中常用短波天线的设计与架设

任何无线电通信设备都是通过天线发射电波来传送信息的,因而,它在无线电通信 中占有极其重要的地位．笔者在本文中结合实际工作中的体会讨论了短波天线的类型和基本 特性,并提出了地震通信中常用短波天线的设计方法和架设要求．     

一种自回归GPS校准晶振的实现

本文在已有的GPS测频技术研究成果的基础上,提出了一种简便易行的校频方法。它不需要非常准确的测频设备,仅仅利用GPS信号与石英晶体振荡器输出的频率之间的频差来控制压控晶振,使两者的频差逐步减小。测试结果加,经GPS控制的英晶体振荡器频率准确度可以达到10-11量级。     

电话授时系统用户接收器频率修正及实验研究

商品晶振都存在着频率漂移 ,介绍一种软件修正电话授时用户终端频率线性漂移的方法。并验证了这种方法的实验结果 ,经修正后一天最大偏差优于± 7毫秒。这种方法比较简单 ,切实可行 ,能够满足普通精度用户的要求。     

Dissipative travelling wave solution for El Niño tropic sea-air coupled oscillator

El Niño and Southern Oscillation (ENSO) is an interannual phenomenon involved in the tropical Pacific sea-air interactions. An asymptotic method of solving equations for the ENSO model is proposed. Based on a class of oscillator of ENSO model and by employing a simple and valid method of the variational iteration, the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is studied. Firstly, by introducing a set of functionals and computing the variationals, the Lagrange multipliers are obtained. And then, the generalized variational iteration expressions are constructed. Finally, by selecting appropriate initial iteration, and from the iterations expressions, the approximations of solution for the sea-air oscillator ENSO model are solved successively. The approximate dissipative travelling wave solution of equations for corresponding ENSO model is studied. It is proved from the results that the method of the variational iteration can be used for analyzing the sea surface temperature anomaly in the equatorial Pacific of the sea-air oscillator for ENSO model.     

电磁波发射机的研制及试验结果

电磁波发射机在电磁波观测系统研究项目中起了很好的作用。本文详细介绍了发射机的研制、指标、使用方法及试验结果。     

用状态空间模型递推模拟振荡器噪声

对振荡器的五种噪声之间的关系作了介绍,并对相位时间信号的状态空间模型的基本理论作了描述.在此基础上导出了五种噪声的递推模拟方法.最后模拟了这五种噪声并分析了它们的功率谱.结果表明,功率谱符合这几种噪声的定义.     

YH-1星载超稳定晶振的频率稳定性的测试与分析

中国首个火星探测器萤火1号拟定在2011年发射升空。探测器上配备了一组(2个)超稳定晶体振荡器,该组晶体振荡器为X波段发射机提供频率标准,向地球发射下行信号。地面台站采用无线电开环多普勒和甚长基线干涉测量技术,对其进行通信、导航和跟踪。分析处理了萤火1号的超稳定晶体振荡器频率实验测试数据,确认晶体振荡器的频率稳定度约为1×10~(12),此结果可以作为火星探测器精密测定轨的有力支撑。     

微弱正弦信号检测模型混沌解的判定

运用Melnikov方法就混沌检测模型的混沌判据问题进行研究，证明并推导该数学模型为非线性混沌系统及系统出现混沌状的临界值。为正弦信号的混沌检测和混沌振子法用于准周期信号检测提供理论依据，也为从低信噪比地震勘探资料中提取有效信息建立理论基础。     

Dissipative Travelling Wave Solution for EI Ni(n)o Tropic Sea-air Coupled Oscillator

El Ni(n)o and Southern Oscillation(ENSO)is an interannual phenomenon involved in the tropical Pacific sea-air interactions.An asymptotic method of solving equations for the ENSO model is proposed.Based on a class of oscillator of ENSO model and by employing a simple and valid method of the variational iteration,the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is studied.Firstly,by introducing a set of functionals and computing the variationals,the Lagrange multipliers are obtained.And then,the generalized variational iteration expressions are constructed.Finally,by selecting appropriate initial iteration,and from the iterations expressions,the approximations of solution for the sea-air oscillator ENSO model are solved successively.The approximate dissipative travelling wave solution of equations for corresponding ENSO model is studied.It is proved from the results that the method of the variational iteration can be used for analyzing the sea surface temperature anomaly in the equatorial Pa-cific of the sea-air oscillator for ENSO model.