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1.
A field reconnaissance mission was led to the areas affected by the disaster caused by the Magnitude 7.9 earthquake event of 15/08/2007 near the city of Pisco in Peru. The main objectives of the mission were to collect data and make observations leading to improvements in design methods and techniques for strengthening and retrofit, and to assist the phase of reconstruction. The mission focused on the behaviour of non-engineered structures, in particular those of adobe constructions. The findings of the mission confirmed that most of the damage was observed on adobe houses constructed with traditional non anti-seismic techniques which either collapsed or nearly collapsed, causing 519 deaths, 1,366 injuries and more than 58,000 houses destroyed. The mission also confirmed that buildings constructed according to modern earthquake resistant design standards performed with no evident damage. All the parties contacted during the mission, especially the EC Delegation, showed particular interest in the results of the present mission report, which will be taken into consideration when planning the reconstruction phase, especially of the most distant rural areas, where close collaboration between the Governmental Institutions, International Organizations, Universities and NGO’s, will be needed to assist the population for the adoption of earthquake resistant designs in the reconstruction of the destroyed houses.  相似文献   

2.
本文利用卫星重力反演与模拟软件ANGELS系统(ANalyst of Gravity Estimation with Low-orbit Satellites)对低低跟踪模式的重力卫星的关键载荷精度指标进行了深入分析.模拟结果表明:(1)对短弧长积分法而言,在低低跟踪模式的关键载荷精度指标中,重力场反演精度对星间距离变率精度最为敏感;(2)通过对目前在轨运行GRACE的载荷指标进行分析,发现轨道数据的误差主要影响重力场的低阶部分(约小于25阶),较高阶次部分(约大于26阶)主要受星间距离变率的误差限制;(3)如果下一代低低跟踪模式的重力卫星的目标之一是把重力异常反演精度较GRACE提高约10倍,则在保持轨道高度和GRACE相同的前提下,轨道、星间距离变率和星载加速度计等关键载荷指标需要达到的最低精度分别约为2cm、10nm·s-1和3.0×10-10 m·s-2;(4)轨道精度和混频误差将是影响下一代低低跟踪模式重力卫星重力场恢复能力进一步提高的主要制约因素,距离变率精度和加速度计精度存在盈余.  相似文献   

3.
焦维新  钟俊 《地球物理学报》2016,59(11):3955-3959
从数以万计的近地小行星(NEAs)中选择探测目标,是一项非常重要的工作.选择小行星时需要考虑的主要问题是:NEAs的轨道参数、自旋周期、大小、科学价值、表面特征以及到达NEAs的时间.本文采用排除法从众多近地小行星中确定候选者,并根据科学目标的要求确定最终探测目标.  相似文献   

4.
In November 2012 EEFIT launched its first ever return mission to an earthquake affected site. The L’Aquila Earthquake site was chosen as this is a recent European event of interest to the UK and European earthquake engineering community. The main aims of this return mission were to document the earthquake recovery process and this paper presents an overview of the post-disaster emergency phase and transition to reconstruction in the Aquila area after the earthquake. It takes an earthquake engineering perspective, highlighting areas mainly of interest to the fields of structural/seismic engineering and reconstruction management. Within the paper, reference is made to published literature, but also to data collected in the field during the return mission that would not otherwise have been available. The paper presents some specific observations and lessons learned from the L’Aquila return mission. However, in light of current international efforts in conducting return missions, the paper ends with some reflections on the value that return missions can provide to the field of earthquake engineering in general, based on the EEFIT L’Aquila experience.  相似文献   

5.
传统的WLAN(Wireless LAN无线局域网)因为其单跳的网络特性造成了通讯瓶颈,这也使得其不能很好地满足地震应急救援通讯对效率、准确、安全等特性的要求。一种新型的无线网络形式WMN(Wireless Mesh Network无线网状网)的出现为构建下一代地震应急救援无线通讯系统提供了良好的网络基础。通过对传统地震应急救援无线平台和WMN的介绍,分析了构建新型地震应急救援无线通讯平台的技术指标和可行性,并且给出了平台搭建建议,最后对可能存在的问题以及应用前景进行了讨论。  相似文献   

6.
GOCE卫星重力测量中有色噪声滤波器设计   总被引:1,自引:0,他引:1  
本文根据卫星重力梯度测量的有色噪声特性,设计了Wiener、AR、FIR三种滤波器,并利用模拟的有色噪声数据对其滤波效果进行了测试,结果表明:对于文中采用的有色噪声数据,AR的滤波效果最好,其次为Wiener滤波器,FIR的滤波效果最差;三种滤波器均可用于GOCE卫星重力测量中有色噪声数据滤波,但其实用性尚需利用实测数据进行检验;可以利用不同的滤波器对含有色噪声的卫星重力梯度数据进行多次滤波,以进一步减弱有色噪声对卫星重力梯度测量精度的影响.  相似文献   

7.
Asteroseismology and extrasolar planets are the main science goals of the Eddington mission, now approved by ESA for a 2007 launch. Alan Penny presents a summary of the January 2002 RAS meeting that discussed the sciences of this wide-field high-precision photometric space telescope. Since the date of this meeting, ESA has decided to implement the mission in the framework of a 2007–08 launch.  相似文献   

8.
This contribution investigates two different ways for mitigating the aliasing errors in ocean tides. This is done, on the one hand, by sampling the satellite observations in another direction using the pendulum satellite mission configuration. On the other hand, a mitigation of the temporal aliasing errors in the ocean tides can be achieved by using a suitable repeat period of the sub-satellite tracks.The findings show, firstly, that it is very beneficial for minimizing the aliasing errors in ocean tides to use pendulum configuration; secondly, optimizing the orbital parameter to get shorter repeat orbit mode can be effective in minimizing the aliasing errors. This paper recommends the pendulum as a candidate for future gravity mission to be launched in longer repeating orbit mode with shorter “sub-cycle” repeat periods to improve the temporal resolution of the satellite mission.  相似文献   

9.
10.
“洞察”号任务是火星探测历史上一次巨大的飞跃.本文从介绍“洞察”号的科学目标和火星表面地震观测实验出发,展示“洞察”号地震数据中的发现.受益于“维京”2号的火星探测经验,“洞察”号首次成功监测到了火星震信号,并由此得到了火星壳结构的衰减特征.火星的地震数据中检测到了由气压引起的地表形变和HP3打孔信号,并用于约束登陆点附近表面土层的物理性质和地下结构的反演.此外,使用在2.4 Hz处出现的结构响应能够辨别自然响应和登陆器自振等机械振动.火星的地震数据中也检测出了Glitch和Donk等噪声信号,我们总结了其特征和形成原因.“洞察”号对火星壳的探测比较成功,但是由于缺乏大震级的火星震和陨石撞击事件的记录,对火星深部的了解依然比较有限.  相似文献   

11.
Temporal mass variations in the Earth system, which can be detected from the Gravity Recovery and Climate Experiment (GRACE) mission data, cause temporal variations of geoid heights. The main objective of this contribution is to analyze temporal variations of geoid heights over the area of Poland using global geopotential models (GGMs) developed on the basis of GRACE mission data. Time series of geoid height variations were calculated for the chosen subareas of the aforementioned area using those GGMs. Thereafter, these variations were analyzed using two different methods. On the basis of the analysis results, models of temporal geoid height variations were developed and discussed. The possibility of prediction of geoid height variations using GRACE mission data over the area of Poland was also investigated. The main findings reveal that the geoid height over the area of Poland vary within 1.1 cm which should be considered when defining the geoid model of 1 cm accuracy for this area.  相似文献   

12.
卫星重力探测技术的发展   总被引:2,自引:0,他引:2  
在地球物理勘探领域中,人造地球卫星的发射为重力测量提供了新的途径。与以往探测重力的手段相比,重力卫星的发射大大改善了人们对地球重力场的认识,随着CHAMP、GRACE和GOCE卫星的发射,将把现有静态中长波部分重力场的精度提高1—2个数量级,并提供长波部分重力场随时间变化的信息。卫星重力学对我国的基础测绘服务和国防建设有着重要的实用价值。  相似文献   

13.
The Venus Express mission, currently orbiting Earth's nearest planetary neighbour, has just had its mission extended until the end of 2012 by the European Space Agency (ESA). In December 2010 it will be joined by the Japanese Venus Climate Orbiter, which has similar goals of understanding the atmosphere and climate. In this article Fred Taylor looks at what has been learned so far and what remains mysterious about our nearby twin, with its torrid weather and its global warming issues.  相似文献   

14.
GOCE Data Processing: The Spherical Cap Regularization Approach   总被引:3,自引:0,他引:3  
Due to the sun-synchronous orbit of the satellite gravity gradiometry mission GOCE, the measurements will not be globally available. As a consequence, using a set of base functions with global support such as spherical harmonics, the matrix of normal equations tends to be ill-conditioned, leading to weakly determined low-order spherical harmonic coefficients. The corresponding geopotential strongly oscillates at the poles. Considering the special configuration of the GOCE mission, in order to stabilize the normal equations matrix, the Spherical Cap Regularization Approach (SCRA) has been developed. In this approach the geopotential function at the poles is predescribed by an analytical continuous function, which is defined solely in the spatially restricted polar regions. This function could either be based on an existing gravity field model or, alternatively, a low-degree gravity field solution which is adjusted from GOCE observations. Consequently the inversion process is stabilized. The feasibility of the SCRA is evaluated based on a numerical closed-loop simulation, using a realistic GOCE mission scenario. Compared with standard methods such as Kaula and Tikhonov regularization, the SCRA shows a considerably improved performance.  相似文献   

15.
2005年10月8日巴基斯坦北部发生了7.8级大地震,本文作者在参加中国国际救援队现场地震救援的同时,深入地震重灾分布区开展了工程震害的现场调查工作。本文基于震害调查结果,分析了此次地震灾害状况和工程震灾特点,探讨了其产生的原因,并且给出了一些经验教训。  相似文献   

16.
The fundamental processes that energize, transport, and cause the loss of charged particles operate throughout the universe at locations as diverse as magnetized planets, the solar wind, our Sun, and other stars. The same processes operate within our immediate environment, the Earth's radiation belts. The Radiation Belt Storm Probes (RBSP) mission will provide coordinated two-spacecraft observations to obtain understanding of these fundamental processes controlling the dynamic variability of the near-Earth radiation environment. In this paper we discuss some of the profound mysteries of the radiation belt physics that will be addressed by RBSP and briefly describe the mission and its goals.  相似文献   

17.
A monitoring mission to study the shape and estimate initial dilution of the S. Jacinto outfall plume using an autonomous underwater vehicle (AUV) was performed on July 30, 2002. In order to reduce the uncertainty about plume location and to concentrate the vehicle mission only in the hydrodynamic mixing zone, outputs of a near-field prediction model, based on effective real-time in situ measurements of current speed and direction and density stratification, were opportunistically used to specify in real time the mission transects. The surface characteristics of the outfall plume were found to be influenced strongly by the relatively weak stratification and low current velocities. Dilution was estimated using a temperature–salinity (TS-) diagram with initial mixing lines between wastewater and ambient waters. Effluent dilutions were at least 30:1 in this study. In order to efficiently map the plume dispersion we applied the least-squares collocation method technique. Our results demonstrate that AUVs can provide high-quality measurements of physical properties of effluent plumes in a quite effective manner and valuable considerations about the initial mixing processes under real oceanic conditions can be further investigated.  相似文献   

18.
In the last decade, satellite gravimetry has been revealed as a pioneering technique for mapping mass redistributions within the Earth system. This fact has allowed us to have an improved understanding of the dynamic processes that take place within and between the Earth’s various constituents. Results from the Gravity Recovery And Climate Experiment (GRACE) mission have revolutionized Earth system research and have established the necessity for future satellite gravity missions. In 2010, a comprehensive team of European and Canadian scientists and industrial partners proposed the e.motion (Earth system mass transport mission) concept to the European Space Agency. The proposal is based on two tandem satellites in a pendulum orbit configuration at an altitude of about 370 km, carrying a laser interferometer inter-satellite ranging instrument and improved accelerometers. In this paper, we review and discuss a wide range of mass signals related to the global water cycle and to solid Earth deformations that were outlined in the e.motion proposal. The technological and mission challenges that need to be addressed in order to detect these signals are emphasized within the context of the scientific return. This analysis presents a broad perspective on the value and need for future satellite gravimetry missions.  相似文献   

19.
利用SWARM卫星高低跟踪探测格陵兰岛时变重力信号   总被引:1,自引:0,他引:1       下载免费PDF全文
王正涛  超能芳 《地球物理学报》2014,57(10):3117-3128
GRACE重力卫星任务即将结束,后续GRACE Follow-On卫星计划于2017年发射,在此期间,迫切需要一个新的卫星计划继续对全球时变重力场进行连续监测,以保证时变重力场信息时间序列的连贯性.SWARM计划包括三颗轨道高为300~500 km的近极轨卫星星座,类似于三颗CHAMP卫星,具有接替时变重力场探测的潜力.本文首先分析SWARM(模拟)、CHAMP、GRACE反演至60阶时变重力场球谐系数的误差特性及不同高斯平滑半径对高频误差的抑制效果,然后分别利用SWARM、CHAMP、GRACE的时变重力场模型恢复全球质量变化,结果表明,SWARM模拟观测数据的高频误差低于CHAMP观测数据,探测时变重力场的整体精度优于CHAMP,略低于GRACE探测精度;其次,对比2003年1月—2009年12月期间CHAMP(hl-SST)和GRACE(ll-SST)时变重力场模型反演格陵兰岛冰盖质量变化趋势,结果显示,CHAMP数据得到格陵兰岛冰盖质量变化趋势为-50.2±2.0 Gt/a,GRACE所得结果为-41.2±1.6 Gt/a,两者相差21.8%;最后,对比2000年1月—2004年12月间SWARM模拟数据和"真实"模型数据反演的格陵兰岛冰盖质量变化趋势,结果表明,两者相差19.2%.本文研究表明,利用SWARM hl-SST数据探测时变重力场可以达到20%相对精度水平,有潜力用于填补GRACE和GRACE Follow-On期间探测地球时变重力场的空白.  相似文献   

20.
赵倩  苏小宁 《地震》2016,36(3):152-160
从满足重力卫星编队的轨道根数条件出发, 通过全过程动力法仿真实验, 计算得出了满足串联编队(GRACE-type)、 钟摆编队(Pendulum-type)和车轮编队(Cartwheel-type)这三种卫星编队模式稳定在轨的轨道参数, 并验证了其稳定性。 同时, 深入分析了各种卫星编队模式对于重力卫星任务的适用性, 结果表明, 同时包含两个方向观测量的Pendulum-type编队和Cartwheel-type编队, 能够在一定程度上克服GRACE-type编队中存在的由单一星间观测量的强相关性导致的重力场各向异性敏感度问题, 是理论上更适合重力探测任务的卫星编队模式。  相似文献   

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