87型钻孔数字测温仪简介

中国科学院地球物理研究所最近研制出87型钻孔数字测温仪。该仪器主要由感温探头,测量电路、A/D转换、小数点驱动、显示、编码、打印接口和打印机等部分组成,其工作原理为:感温探头和测量电路将被测温度变为模拟电压信号,经A/D转换和小数驱动电路又转变为数字量字段码,一路送显示器直接显示出被测温度数值,另一路送编码器,将字段码转     

MFT-PT型组合多路遥测仪

MFT-PT型遥测仪的研制,是为了在较大范围内（100-200公里）同时传输观测短周期、长周期地震信号和其他地球物理量. 该仪器系统是由脉冲幅度调制和频率调制两种遥测系统复合组成的.其设计特点有如等待式多相多谐振荡器,单管单稳电路等.遥测仪与电子计算机,磁带机配用可以达到快速综合处理地震信号的目的. 该仪器如果采用话音频率,则可以利用电话线路把地震信号送到几千公里之外.遥测仪如果与射频收发讯机配合,则可以构成无线流动台网.     

海城震区深地震测深资料A/D转换方法及其效果的研究

介绍深地震测深模拟磁带资料在CROMEMCO型微机上实现A/D转换的方法及其效果。在实现A/D转换研究中,进行了时标信号采集方式、六响信号处理、模拟回放电路改进等方法的试验,从而提高了A/D转换精度与效果。经对海城震区实际资料分析可知:该系统A/D转换精度达到了规范要求。     

基于STM32和LabVIEW的双频激电信号采集系统设计

本文将LabVIEW与基于32位ARM单片机的数据采集电路结合,研究实现了一种高精度、多功能的双频激电信号采集系统.激电信号被采集系统接收后,经信号调理进入模数转换电路转换为数字信号,由USB接口送入基于LabVIEW软件平台的上位机中.上位机对该信号进行滤波选频、幅值测量、频谱分析、幅频率计算等处理,得到目标参数,同时还具有绘图、保存、查看等功能.本文就双频激电信号采集进行了阻容网络模拟实验,先用公式计算出理论视幅频率值,然后搭建电路进行实测.实验结果表明,该采集系统对双频激电信号采集的视幅频率测量误差小、精度高,具有良好的测量效果.     

IPSTAR卫星在高斯信道中传输数据应用与性能分析

IPSTAR系统由IPSTAR号卫星、地面业务关口站和小口径天线地面终端组成.本文通过建立调制方式模型和高斯信道模型,分析卫星信号信噪比及传输性能,对比信噪比不同的星座图,分析卫星通信系统使用QPSK调制方式调制、传输地震数据对信号的影响,为使用卫星通信系统传输地震数据提供理论依据.     

SeisProc：基于ObsPy库的地震数据处理软件

在已有地震数据处理软件的基础上,为了进一步丰富和完善地震数据处理工具库,基于ObsPy模块库,设计并实现了一款简单易用、可拓展的地震数据处理软件SeisProc。该软件利用ObsPy提供的信号接口,实现了对多种格式的地震数据文件的预处理功能,应用PyQt5库设计GUI,实现数据预览、格式转换、波形绘制和预处理等功能。     

人工爆炸地震野外数据处理装置

1988年底在华南地区连县-港口近400km的测线上,首次使用了中国科学院地球物理研究所研制的人工爆炸地震野外数据处理装置.该装置由AT型微机及必要的接口板和外围装置组成,能在野外条件下把模拟或数字记录仪记录结果以数字数据形式输入计算机,并进行显示、打印、存储等操作.由于成功地解决了诸如磁带信号直接屏幕扫描搜寻,时间信号自动识别、解码,钟差和零时信号屏幕光点比测,采样率随磁带速度自动调节,多通道长时间信号连续存储,数字滤波和再采样,用普通打印机快速打印高分辨率图形等技术问题,我们在野外记录后2-3天内即能绘出全测线120道记录的剖面图,达到了前所未有的高速度.     

海底可控源电磁接收机的姿态记录装置

用于观测海洋可控源电磁信号的海底可控源电磁接收机,由于投放过程的随机性,需要借助专门的姿态模块获取位于海底的接收机工作过程中所处的三轴姿态信息(方位角、俯仰角、横滚角).受底流冲击及底质不稳等因素影响,接收机可能在海底发生位移,因此有必要连续观测其三轴姿态信息.该姿态记录装置由水下单元和甲板单元组成,其中甲板单元为水下单元提供时间服务;甲板单元由密封盒、水密电缆、时间服务电路组成.水下单元硬件由压力舱、锂电池组、姿态记录电路、水密接插件组成;水下单元重点解决了高精度三轴姿态观测、长时间连续工作、大容量存储等技术难题.并为姿态记录装置开发了用户显控软件,用于实现数据传输、显示、回放、成图、格式转换等功能.该装置典型技术指标为观测角度误差:±1°,连续工作时间:40day(1min采样间隔),存储空间:64 MB,用户接口:USB2.0,工作水深:2000 m,水中重量:100g.2014年进行的海洋试验验证了该装置的有效性及可靠性.     

闪电与罗兰C信号接收处理系统

基于C/S模式架构,设计闪电与罗兰C信号接收处理系统,并阐述系统中数据采集模块、分析与计算模块、存储与回放模块、多台站数据匹配模块的作用和功能。该系统在安徽省地震局运行以来,工作状态良好,达到设计要求。     

用于电磁法观测系统开机自检的信号发生器实现方法

针对电磁法观测系统在使用过程中的开机自检要求,分析常用测量系统及地球物理仪器的检测信号特征,通过对已有机制进行研究和对比,结合现有信号产生电路的优势,提出一种功耗低、精度高、设计简单的自检信号发生器实现方案.基于该方案设计了一套实现电路,其以CPLD为核心,由精密参考电压源、模拟开关及运算放大器等器件构成,并对该电路进行仿真与测试.通过系统稳定性分析,采用波特图与奈奎斯特图表明信号发生电路的稳定性符合设计要求.经仿真与测试,能够通过换挡开关产生幅值为20μV～2 V、频率范围在1 Hz～100 kHz的自检脉冲信号,频率稳定在1%,重复测试相位稳定度小于1.5%,幅值误差可以优化到1%以内,且能通过其稳定的谐波分量来获取该系统带宽更宽的通道测试响应.测试结果表明,该自检信号发生器电路实际功耗小于0.3 W,20μV～2 V幅值范围和1 Hz～100 kHz频率范围内性能指标的测量结果和仿真结果相符,并成功应用于某监控系统.利用该信号发生器电路实现自检具有操作方便、成本低、易于设计等优点,能够有效的弥补其它自检模式的缺陷.     

A Monte Carlo study of rainfall forecasting with a stochastic model

A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.     

Earthquake Engineering and Engineering Vibration Aims And Scope

正This journal is established by the Institute of Engineering Mechanics(IEM),China Earthquake Administration,to promote scientific exchange between Chinese and foreign scientists and engineers so as to improve the theory and practice of earthquake hazards mitigation,preparedness,and recovery.To accomplish this purpose,the journal aims to attract a balanced number of papers between Chinese and     

Foreword

Destructive earthquakes have caused great damage in China and the United States and collapsing buildings havecaused many deaths and injuries. The field of earthquake engineering studies earthquake hazards, the occurrence ofearthquakes of various magnitudes, the nature of the ground shaking during an earthquake, the vibration of structuresduring earthquakes, the strengthening of existing structures and the design of new structures to be earthquake resistant,and finally, how to cope with earthquake damage and restore a city to normal functioning. Such efforts are in progressin both countries, but unfortunately, the language barrier interferes with the free flow of information between China andthe Untied States. It would be mutually beneficial if some means could be developed to promote the exchangeof information across the Pacific Ocean. This new journal has been established for this purpose and its success willbe an important step in promoting earthquake engineering in China and the United States.     

WORLD ASSOCIATION FOR SEDIMENTATION AND EROSION RESEARCH(WASER)

正President:Giampaolo Di Silvio,Italy Vice Presidents:Ulrich C.E.Zanke,Germany Zhao-yin Wang,China The World Association for Sedimentation and Erosion Research(WASER),inaugurated on Oct.19,2004,is an independent non-governmental,non-profit organization.The mission of WASER is to promote international co-operation on the study     

Enhancing remote sensing research on global change to improve our understanding on Earth system processes

正Global Change includes climate change and other environmental changes caused by the joint interaction among various layers of Earth. From the positive side, global change provides new opportunities to human and other living forms on Earth. In the meantime, it creates tremendous challenges and negative impact. At present, the negative impacts have reached all primary processes of the global ecosystem and every aspect of human society, especially causing degradation of the ecosystem. For instance, intensive deforestation causes decline of biodiversity; global warming causes sea level rise and increases     

SCIENCE CHINA Earth Sciences SUBJECT INDEX TO VOLUME 57(2014)

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