JOPENS流服务与TDE-324系列地震数据采集器实时数据流接口程序的设计与实现   总被引：1，自引：0，他引：1  

吴永权  黄文辉 《华南地震》2011,31(3):50-59

JOPENS系统是为地震台网中心开发的数据处理软件系统,为使地震台站记录到的实时数据流能接入JOPENS系统处理,必须为数采开发对应的接口程序,用来接收地震台站数采的实时数据流.介绍了JOPENS的流服务与珠海泰德公司生产的TDE-324系列数采实时数据流接口的设计思想与实现过程,并对接口程序进行了故障处理能力试验检测...  相似文献   

浅谈新疆测震台网传输链路的改造     

袁顺 《内陆地震》2011,(4):373-378

要做到IP到台站有很多种方式可选,根据新疆测震台网各台站的现状列举了7类不同的数据传输方式,这些数据传输方式在新疆测震台网中均得到应用,也都达到IP到台站的目的.分别对这些数据传输链路的原理及优缺点进行阐述,并结合目前各台站具体情况作链路适用性的相关分析,希望能够对其他省局台网的台站通信链路设计、改造起到参考.  相似文献   

基于DTU的加速度强振动记录终端的设计     

吴林斌  陈志高  关伟智  吕瀚  李家明  吴雄伟 《大地测量与地球动力学》2011,31(Z1):155-156,164

设计基于DTU的强振记录终端,采用SOC系列C8051F015型单片机对MEMS加速度计的输出信号进行A/D转换,监测待测体所经受的强振加速度值,并通过DTU内嵌的GPRS无线网络通讯方式将数据发送到远程数据中心.该系统具有体积小,安装与操作方便,免维护等特性.  相似文献   

变分连续同化中优化步长的推导方法及数值试验   总被引：1，自引：0，他引：1  

王云峰  伍荣生  王元  潘益农 《大气科学》2004,28(3):415-423

一个好的变分同化方法,必须考虑到预报模式具有误差,并对模式误差进行纠正.变分连续同化(VCA)通过在模式方程中引进一个修正项,连续地调整模式变量,从而达到以上目的.在变分连续同化的迭代过程中,优化步长的选取方法对于同化迭代是否收敛、收敛速度快慢与否都至关重要,文中推导了一种有效利用观测资料计算优化步长的新方法,并以大气运动方程中一维非线性平流波和二维惯性波为例,进行了四维变分资料同化数值试验.数值结果表明,VCA方法和计算优化步长的公式都是有效的.  相似文献   

“Pilot chimney” on the waterloo campus     

G. T. Csanady 《大气与海洋》2013,51(1):18-19

A brief survey is given of the sources, the methods of injection into the atmosphere, and the mechanisms of deposition into bodies of water for various atmospheric pollutants which contribute significantly to the pollution of large bodies of water. Specific examples of the relative importance of atmospheric sources are included where data are available. Programs of the Canadian Atmospheric Environment Service in this field of research are outlined.  相似文献   

雷达反射率资料的三维变分同化研究   总被引：6，自引：3，他引：3  

范水勇  王洪利  陈敏  高华 《气象学报》2013,71(3):527-537

应用天气研究和预报模式(WRF)三维变分系统中一种新的雷达反射率资料间接同化方法来进行反射率资料的三维变分同化研究,评估雷达反射率资料对夏季短时定量降水预报的作用.该方法不直接同化雷达反射率资料,而是同化由反射率资料反演出的雨水和估计的水汽.以2009年夏季北京地区发生的4次强降水过程为例,考察了北京市气象局业务运行的快速更新循环同化预报系统对京津冀地区雷达网的雷达反射率资料的同化性能以及雷达反射率资料和径向风资料同时同化的效果.数值试验结果表明:(1)同化反演雨水或水汽都能改善降水预报,但同化反演水汽对降水预报效果的改善起了更重要的作用;(2)同化反射率资料能极大地提高短时降水预报的效果,其稳定的正面效果可以延伸到6h的预报时效,而同化径向风资料不能得到稳定的正效果;(3)同化雷达资料时,应用快速更新循环同化预报系统是提高短时定量降水预报的一个有效途径.  相似文献   

Assimilating Best Track Minimum Sea Level Pressure Data Together with Doppler Radar Data Using an Ensemble Kalman Filter for Hurricane Ike (2008) at a Cloud-Resolving Resolution          下载免费PDF全文

XUE Ming  DONG Jili 《Acta Meteorologica Sinica》2013,27(3):379-399

Extending an earlier study, the best track minimum sea level pressure (MSLP) data are assimilated for landfalling Hurricane Ike (2008) using an ensemble Kalman filter (EnKF), in addition to data from two coastal ground-based Doppler radars, at a 4-km grid spacing. Treated as a sea level pressure observation, the MSLP assimilation by the EnKF enhances the hurricane warm core structure and results in a stronger and deeper analyzed vortex than that in the GFS (Global Forecast System) analysis; it also improves the subsequent 18-h hurricane intensity and track forecasts. With a 2-h total assimilation window length, the assimilation of MSLP data interpolated to 10-min intervals results in more balanced analyses with smaller subsequent forecast error growth and better intensity and track forecasts than when the data are assimilated every 60 minutes. Radar data are always assimilated at 10-min intervals. For both intensity and track forecasts, assimilating MSLP only outperforms assimilating radar reflectivity (Z) only. For intensity forecast, assimilating MSLP at 10-min intervals outperforms radar radial wind (Vr) data (assimilated at 10-min intervals), but assimilating MSLP at 60-min intervals fails to beat Vr data. For track forecast, MSLP assimilation has a slightly (noticeably) larger positive impact than Vr(Z) data. When Vr or Z is combined with MSLP, both intensity and track forecasts are improved more than the assimilation of individual observation type. When the total assimilation window length is reduced to 1h or less, the assimilation of MSLP alone even at 10-min intervals produces poorer 18-h intensity forecasts than assimilating Vr only, indicating that many assimilation cycles are needed to establish balanced analyses when MSLP data alone are assimilated; this is due to the very limited pieces of information that MSLP data provide.  相似文献   

Using a H∞ filter assimilation procedure to estimate root zone soil water content     

Haishen Lü  Xiaoli Li  Zhongbo Yu  Robert Horton  Yonghua Zhu  Zhenchun Hao  Long Xiang 《水文研究》2010,24(25):3648-3660

Root zone soil water content impacts plant water availability, land energy and water balances. Because of unknown hydrological model error, observation errors and the statistical characteristics of the errors, the widely used Kalman filter (KF) and its extensions are challenged to retrieve the root zone soil water content using the surface soil water content. If the soil hydraulic parameters are poorly estimated, the KF and its extensions fail to accurately estimate the root zone soil water. The H‐infinity filter (HF) represents a robust version of the KF. The HF is widely used in data assimilation and is superior to the KF, especially when the performance of the model is not well understood. The objective of this study is to study the impact of uncertain soil hydraulic parameters, initial soil moisture content and observation period on the ability of HF assimilation to predict in situ soil water content. In this article, we study seven cases. The results show that the soil hydraulic parameters hold a critical role in the course of assimilation. When the soil hydraulic parameters are poorly estimated, an accurate estimation of root soil water content cannot be retrieved by the HF assimilation approach. When the estimated soil hydraulic parameters are similar to actual values, the soil water content at various depths can be accurately retrieved by the HF assimilation. The HF assimilation is not very sensitive to the initial soil water content, and the impact of the initial soil water content on the assimilation scheme can be eliminated after about 5–7 days. The observation interval is important for soil water profile distribution retrieval with the HF, and the shorter the observation interval, the shorter the time required to achieve actual soil water content. However, the retrieval results are not very accurate at a depth of 100 cm. Also it is complex to determine the weighting coefficient and the error attenuation parameter in the HF assimilation. In this article, the trial‐and‐error method was used to determine the weighting coefficient and the error attenuation parameter. After the first establishment of limited range of the parameters, ‘the best parameter set’ was selected from the range of values. For the soil conditions investigated, the HF assimilation results are better than the open‐loop results. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

中国海及邻近海域卫星观测资料同化试验   总被引：4，自引：0，他引：4  

何忠杰  韩桂军  李威  李冬  张学峰  王喜冬  吴新荣 《中国海洋大学学报(自然科学版)》2010,40(9)

利用1个基于POMgcs海洋模式和多重网格三维变分同化方法建立的中国海及邻近海域海面高与三维温盐流数值预报模型,通过一系列数值试验,研究了同化卫星测高和卫星遥感海面温度观测资料对该模型预报能力的影响。试验结果表明,同化卫星测高资料可明显改善海面高度与三维温度和盐度的分析预报效果,使1 200 m以上的温度预报误差减小0.16℃,并能有效提高对海洋中尺度现象的预报能力;同化卫星遥感海面温度对100 m以上的温度和盐度的预报效果有所改善,可使海面温度的预报误差减小10%。  相似文献   

Application of FY-2C Cloud Drift Winds in a Mesoscale Numerical Model     

LI Huahong  WANG Man  XUE Jishan  QI Minghui 《Acta Meteorologica Sinica》2010,24(6):740-748

Statistical tests and error analysis of cloud drift winds(CDWs) from the FY-2C satellite were made by using radiosonde observations.According to the error characteristics of the CDW,a bias correction using the thermal wind theory was applied in the data quality control.The CDW data were then assimilated into the GRAPES-meso model via the GRAPES-3DVar.A torrential rain event that occurred in northwestern China during 1-2 July 2005 was simulated.The results indicate that the CDW data were mainly distribute...  相似文献