成都市遥测地震台网通讯方式现状与思考

随着各种数据传输技术的不断成熟和发展,越来越多的数据传输方式在地震监测中得到了广泛应用。本文简要介绍了在地震监测台网中得到实际应用的几种数据传输方式的技术特点和组网方式。同时,将超短波传输、CDMA传输、DDN传输在成都市遥测地震台网中的实际运行情况及传输性能进行比较。     

地震前兆和地震观测的数字化传输

地震前兆和地震观测的数字化传输１．引言地震观测在经历了沙盘记录、薰烟记录、电子放大等模拟记录阶段后，在１９世纪七十年代初，国外已不断地对地震观测数字化传输进行研究与应用。国内在“７６８”工程建设中，作为全国六大区域台网之一的兰州地震遥测台网，也受命进...     

国家数字地震台网中心技术系统与服务

概述中国数字地震观测系统主要是由国家数字地震台网、区域数字地震台网、流动数字地震台网、数字强震台网和区域数字地震台阵、中国地震局卫星数据通信网组成。国家数字地震台网中心是国家数字地震台网、区域数字台阵和数字强震台网数据的集中收集和处理中心 ,同时还保存一部分区域数字地震台网和流动数字地震台网的数据 ,与各区域数字地震台网中心进行各种数据交换 ,另外 ,国家数字地震台网中心也为防震减灾中心的地震应急信息快速响应系统及时提供各种测震数据。国家数字台网中心是我国数字地震观测数据的收集、管理、保存、处理和提供各…     

新疆乌鲁木齐区域数字遥测地震台网

新疆乌鲁木齐区域数字遥测地震台网(以下简称区域台网)是在模拟遥测地震台网的基础上改造、扩建而成的。区域台网由数字汇集中心、4个中继站、12个遥测子台和9个准实时远程子台组成。中国地震局港震公司提供地震计、数据采集器和应用软件，新疆地震局与厂家共同研制无线同步传输设备。区域台网的技术系统采用了先进的数字地震观测技术，具有宽频带、大动态、高精度、高分辨率的特点，以无线实时传输台网为主，远程扩展子台为辅，构成了全国最大的省级台网。2001年4月22日，乌鲁木齐区域数字遥测地震台网通过了中国地震局专家组验收。     

中国数字地震台网所使用的仪器及其传递函数的计算方法

2000年以来我国地震观测系统得到了迅速的发展,目前,已建成了由国家数字地震台网,区域数字地震台网,火山数字地震台网和流动数字地震台网组成的新一代中国数字地震台网。本文介绍了中国数字地震台网的仪器配置情况和各种仪器的主要参数,并结合我国数字地震台网中使用的地震观测系统,阐述了仪器传递函数的计算方法。     

丹江口水库区地震观测30年

介绍了近３０年来丹江口水库区地震观测台网完整记录到的蓄水过程的水库诱发地震序列，回顾了地震观测台网的建设和调整过程，阐明了所取得的观测成果和存在的问题。最后讨论了如何完善地震观测台网等问题。     

数字地震仪器的管理维护及在观测应用中的几点体会

“九五”期间，我国建立了数字地震观测台网。在模拟地震观测向数字地震观测的转变中，从仪器的管理维护到地震的观测分析有许多地方需要不断地改进与完善。我台用数字地震仪观测一年多来，积累了一定经验，摸索了一些排除故障解决问题的方法。总结于此，以便于借鉴。     

地震观测仪器的MiniSEED数据格式的实现

为适应地震观测台网的数字化、标准化和数据网络资源共享的要求,研究实现了在地震观测仪器的Linux系统中直接生成MinisEED数据格式,使数据的记录、网络化传输和接收处理更为快捷、准确,适用于地震观测仪器的实时数据交换与存储.     

南北地震带地震强化监测及技术途径——动态虚拟数字地震台网技术

在2004年5～7月采用全新的思路和技术集成实现了南北地震带紧急强化地震观测。其中的4个关键技术集成是：采用了移动通讯技术解决边远山区地震信号实时传输问题、在Internet中建设VPN（Virtual Private Net）通道解决大型台网之间的数据实时共享问题,采用类LISS数据流形成大型台网地震台站间数据流协议,通过1P到台站技术实现对流动加密台站的远程控制。这4种关键技术的有机集成成功地解决了一系列地震遥测技术领域中的老大难问题,并在3个月内建成了南北地震带动态虚拟数字地震台网。     

重庆地震台网双链路备份传输方案及成效

简要对比DDN、SDH光纤、卫星和无线CDMA等几种通讯方式的优缺点,介绍重庆区域测震台网所使用的传输方案,即以SDH光纤传输为主、无线CDMA为辅的双链路备份传输方案。重点介绍该传输方案的原理和实施方法,详细讲述台站及台网中心的路由配置和相关说明。通过在重庆市区域测震台网的运行,结果发现,传输效果较理想,测震台网台站运行率均达到98%以上,证明了该方案应用的可行性。     

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     

Solute concentrations in the lower niger river and the source rock contribution

Water quality analyses for the Niger River for the 1980/81 hydrological year are presented. The samples were collected from the main river at Lokoja, and from two main tributaries, the Kaduna and the Benue Rivers. Different water types were distinguished by the concentrations of major ions. The type Ca > Na > Mg > K - HCO₃ > SO₄ > Cl was represented at all stations during at least part of the year. Chloride was found to dominate the sulphate ion in the Kaduna and Niger, while the Benue maintained a higher concentration of sulphate relative to chloride all year round. Distinct patterns of seasonal variation in the ion concentrations were observed, particularly for the samples collected at Lokoja. Low ion concentrations were prominent during periods of high discharge, while low flow periods coincided with high dissolved ion concentrations. The contribution of rainwater to the total dissolved solids in the river waters was assessed indirectly using rainwater chemistry data from the Gulf of Guinea. The estimated rainwater contribution to the Lower Niger amounts to 5.15 mg 1^?1. Geochemical weathering calculations involving reactions of the four major minerals of granitic rocks - anorthite, biotite, albite, and K-feldspar - with carbon dioxide and water, can account for the average water composition of the Lower Niger. The proportion of the ionic components was also related to the occurrence of the respective element in the minerals.