基于Linux字符设备的数字地震仪参数模型

地震仪器在长期稳定运行的过程中, 系统参数的有效管理发挥着重要的作用。 针对地震数据采集器EDAS-24IP参数管理模型的一些问题, 开发出了一种新型的基于Linux字符设备的数字地震仪参数模型, 该模型在稳定性、 易用性、 实时性等方面都比原有模型有了很大的提高, 不会出现由于参数文件丢失而导致系统无法重新启动的问题。     

Preliminary Analysis of the Relationship between the Magnitude Deviation of the Station and Site Response in the Fujian Digital Seismic Network

Using the records of 3,069 regional earthquake events from the Fujian Digital Seismic Network from October 2008 to December 2015,in which the magnitude of each of the events was measured by at least six stations,statistics are taken on the deviation between the magnitude of a single station and the average magnitude of the network. It is found that the magnitudes average deviation of each station is-0. 31-0. 68. Statistics are also taken for the period corresponding to the maximum amplitude of the record measured in each station for calculating the magnitude,and the dominant period gained is 0. 06s-0. 38s; site response of each seismic station is inverted using the Moya method,and it is found that the site response of 98 stations is in the bands of 1-20 Hz,suggesting that the site has an amplifying or suppressing effect on the signals in certain frequency bands;Considering the site response corresponding to the inherent 0. 8s period of the WoodAnderson pendulum seismograph,and comparing the magnitude deviation caused by the site response corresponding to the dominant period time of each station with the average magnitude deviation, we obtain that there is a good linear relationship between the magnitude deviation from the dominant period site response and the average deviation of the magnitude of each station,indicating that the magnitude deviation of a single station has a close relationship with the site response of the period corresponding to the maximum amplitude measured for calculating the magnitude.     

基于数字图像测量系统的三轴试样变形研究

基于亚像素角点检测的图像测量技术能够记录试样表面方块角点每一时刻的位移,从而获得试样的表面应变场。将基于试样表面6行方块分别计算的应变与基于全部6行方块的整体平均计算得到的结果进行比较,显示中间4行方块区域的变形基本不受端部约束影响。还对采用试样上、中、下三个部分与整个试样的测量结果获得的应力与应变特性进行了对比分析。该方法能够测量任意时刻试样的轴向应变场,通过轴向应变场的变化可以准确地描述试样剪切带的产生、发展以及完全形成的全过程。     

数字地震台实时处理软件的研制

本软件作为对北京港震机电技术公司软件系统的一个补充，在中文Windows下研制，适用于数字地震台进行数字地震信号实时连续接收和处理。软件的研制充分考虑了台站应用的特点和需求，引入完整的软件工程学理念，采用了面向对象（OOP）的分析设计方法和软件组件技术（COM）。     

山西大同数字地震台网监测能力分析

根据台网布局和实际使用参数,运用反推方法,对大同数字遥测地震台网和模拟遥测地震台网的监控能力进行了计算分析,粗定了数字台网速报表任区的范围,并对数字台网的大震响应能力进行了讨论,结果表明,大同数字台网的监控能力较模拟台网有了较大的提高,整个网内及网缘地震的监控能力为２．０级,网内大部分区域及东部网缘区域可达１．５级;数字台网对网内最大的测定能力为５．０级,网内南部区域可达５．５级;对于网内更大震级的地震,记录将全部限幅,测定震级困难,对山西北部５．５级以上地震要靠山西台网中北部台站来控制。     

数字与模拟地震台网记录的震相特征与地震参数对比分析

本文对辽宁数字与模拟地震台网从1998年12月至1999年5月记录到震波特征、地震参数进行初步的比较与分析。     

印度洋9.0级大地震激发的地球球型振荡和环型振荡

综合分析了中国数字地震台网（CDSN）改造后的5个长周期地震仪台站观测的3天的VHZ、VHE和VHN波形资料,利用功率谱密度估计方法,在没有对资料进行去固体潮处理的情况下,准确获得了2004年12月26日印度洋地震激发的0S3~0S78的基频球型振荡和部分谐频球型振荡和0T3~0T67的基频环型振荡,并与地球初步参考模型（PREM）的理论自由振荡周期进行了对比,发现实测振荡周期与PREM预测的振荡周期符合的很好.频率与PREM模型略微不一致的球型或环型振荡可以解释为地球介质的横向不均匀性和各向异性所致.因此地球自由振荡信息可用于揭示地球的三维不均匀结构信息或各向异性信息,并可能对区分地幔对流模式有所帮助.     

Topography and morphodynamics in the German Bight using SAR and optical remote sensing data

Morphological changes in coastal areas, especially in river estuaries, are of high interest in many parts of the world. Satellite data from both optical and radar sensors can help to monitor and investigate these changes. Data from both kinds of sensors being available for up to 30 years now, allow examinations over large timescales, while high resolution sensors developed within the last decade allow increased accuracy. So the creation of digital elevation models (DEMs) of, for example, the wadden sea from a series of satellite images is already possible. ENVISAT, successfully launched on March 1, 2002, continues the line of higher resolution synthetic aperture radar (SAR) imaging sensors with its ASAR instrument and now also allows several polarization modes for better separation of land and water areas. This article gives an overview of sensors and algorithms for waterline determination as well as several applications. Both optical and SAR images are considered. Applications include morphodynamic monitoring studies and DEM generation.

Distributed geospatial information processing: sharing distributed geospatial resources to support Digital Earth

Abstract

This paper introduces a new concept, distributed geospatial information processing (DGIP), which refers to the process of geospatial information residing on computers geographically dispersed and connected through computer networks, and the contribution of DGIP to Digital Earth (DE). The DGIP plays a critical role in integrating the widely distributed geospatial resources to support the DE envisioned to utilise a wide variety of information. This paper addresses this role from three different aspects: 1) sharing Earth data, information, and services through geospatial interoperability supported by standardisation of contents and interfaces; 2) sharing computing and software resources through a GeoCyberinfrastructure supported by DGIP middleware; and 3) sharing knowledge within and across domains through ontology and semantic searches. Observing the long-term process for the research and development of an operational DE, we discuss and expect some practical contributions of the DGIP to the DE.     

“数字城市”地理空间数据基准研究

针对"数字城市"建设中地理空间数据基准存在的问题,提出基于CGCS 2000建立新地理空间数据基准的解决对策,从基准上解决数字城市互通互联问题,使地方与国家基准保持相对统一。探讨大地基准常用建立方法,总结一套适用"数字城市"通用算法,并以某城市数据为例,分析不同算法的差异,得出了新基准有利于减少长度变形影响的结论。