共查询到20条相似文献，搜索用时 31 毫秒
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2021年2月13日晚,日本福岛县近海发生M7.3级地震,产生强烈振动,此次地震被认为是"3.11"地震的余震。首先介绍了PLUM方法的原理及日本气象厅地震预警系统对于PLUM方法的应用,评述了JMA地震预警结果。通过模拟PLUM方法在此次地震中的表现,由预测精度和有效预警时间两个指标来评估该方法的性能,并与日本气象厅发布的预警信息对比。模拟结果显示:受限于地震数据以及PLUM方法本身的原理,在震后第24 s发出第一次警报,不及使用P波预警与PLUM相结合的JMA地震预警系统及时。在地震前期0~40 s处于烈度剧烈上升阶段,预测精度较差;40 s之后的预测结果较为准确,预测精度高达100%。PLUM方法可以有效克服点-源模型中的弊端,特别是在多个地震同时发生的情况下预警效果良好,将PLUM方法纳入我国地震预警系统可以有效提高预警能力。 相似文献
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It is clear that the basic countermeasure against earthquake strong motion is to reinforce buildings and other structures. Realtime earthquake disaster prevention is a countermeasure during the earthquake itself and is different from realtime seismology. An EEW, earthquake early warning system, is required to trigger realtime earthquake disaster prevention. It is important to avoid too much trust in EEW for the disaster prevention. This paper describes the concept of an EEW and gives a brief history, which eventually led to the development of the UrEDAS, the urgent earthquake detection and alarm system, the first operational P-wave early warning system. A real-world example of disaster prevention by this system is described. Finally, the role of national or public organizations in earthquake disaster prevention will be discussed, with special emphasis on the situation in Japan. 相似文献
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Earthquake early warning systems have been developed to help minimize the loss of life and other damages resulting from catastrophic earthquakes. In the past several decades, these systems have evolved to function using a variety of methodologies. This study introduces an onsite system developed from a correlation between the precursor measurement (Pd3) and the peak ground acceleration (PGV) from 780 historical earthquake events recorded in Taiwan, Japan and South California. The study analyzes and integrates the uncertainty of the onsite system, establishing the statistical relationship between the PGV forecast, the Pd3 precursor, and the exceedance probability (PE). A method is presented for forecasting the PGV by scaling the Pd3. Furthermore, this study also suggests a decision-making model to determine whether or not the early warning notification should be issued, based on factors such as the uncertainty of the early warning system, the magnitude of the precursor, and warning recipient characteristics. 相似文献
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传统地震预警方法通过在地震频发区域部署高密度地震监测台网,进而构建区域地震预警系统。但此方法所需投资较高,同时还需要政府和不同行业间的密切合作,使得大部分位于地震频发区域的国家和地区无力支撑地震预警系统的建设与运维。随着微机电系统技术的发展以及智能手机的普及,地震预警技术出现了新的研究方向,利用智能手机开展地震预警具有巨大的发展潜力。迄今为止,国内外已研发完成多款诸如MyShake、i-jishin之类的手机端APP地震预警软件。本文详细描述了利用手机端内嵌MEMS芯片开展地震预警的研究进展,较为系统地总结了在手机端进行地震预警时所涉及的处理流程以及相关算法。 相似文献
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From the literature, we found that PGV–PD3 regressions for on-site earthquake early warning (EEW) can be quite different depending on the presumption whether or not PGV–PD3 data from different regions should be “mixable” in regression analyses. As a result, this becomes a source of epistemic uncertainty in the selection of a PGV–PD3 empirical relationship for on-site EEW. This study is aimed at examining the influence of this epistemic uncertainty on EEW decision-making, and demonstrating it with an example on the use of PGV–PD3 models developed with data from Taiwan, Japan, and Southern California. The analysis shows that using the “global” PGV–PD3 relationship for Southern California would accompany a more conservative EEW decision-making (i.e., early warning is activated more frequently) than using the local empirical model developed with the PGV–PD3 data from Southern California only. However, the influence of this epistemic uncertainty on EEW is not that obvious for the cases of Taiwan and Japan. 相似文献
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Claudio Satriano Luca Elia Claudio Martino Maria Lancieri Aldo Zollo Giovanni Iannaccone 《Soil Dynamics and Earthquake Engineering》2011
PRESTo (PRobabilistic and Evolutionary early warning SysTem) is a software platform for regional earthquake early warning that integrates recently developed algorithms for real-time earthquake location and magnitude estimation into a highly configurable and easily portable package. The system is under active experimentation in Southern Italy on the Irpinia Seismic Network (ISNet), which is deployed in a seismogenic area that is expected to produce a large earthquake within the next 20 years. In this paper we describe the architecture of the system and test its performances using both small earthquakes (M<3.5) recorded at the ISNet and a large event recorded in Japan, through a simulation mode. The results show that, when a dense seismic network is deployed in the fault area, PRESTo can produce reliable estimates of earthquake location and size within 5–6 s from the event origin. Each estimate is provided as a probability density function, with an uncertainty that typically decreases with time: a stable solution is generally reached within 10 s from the origin. 相似文献
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随着世界上多个国家和地区的地震预警系统投入运行,误报和漏报等问题逐渐突显,特别是将标定以及强干扰波形误识别为大震事件,快速、精确地区分地震与其他波形是一个难题。针对于此,该研究提出了基于卷积神经网络地震波形智能识别方法。首先收集并处理了2012—2017年中国境内福建以及周边邻省共683个地震和478个爆破事件,并对这些样本筛选、截取和基线校正等预处理,共得到了27 500条三通道波形。在此基础上,构建了3 s波形输入的卷积神经网络模型(SW-CNN)。结果表明：模型对地震、噪声、爆破和异常波形的识别率分别为97.9、99、99.2和99.3%。相比于人工手动分类识别,该模型更省时和更稳定,为地震预警目前所面临的问题提供了一个新的解决方法。 相似文献
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地震预警系统的效能评估和社会效益分析 总被引：3，自引：1，他引：2
本文从地震预警系统可减少的人员伤亡和可挽回的经济损失两个角度出发, 研究了地震预警系统的效能和社会效益. 通过对兰州市及周边地区潜在震源各个震级档的年平均发生概率进行计算, 并结合以兰州市为中心布设的80个强震预警台站信息, 计算了有效的预警时间及地震烈度. 基于生命易损性模型方法, 计算了地震预警系统可减少的人员伤亡系数; 采用基于宏观GDP的损失评估方法, 计算了地震预警系统可减少的经济损失, 分析了地震预警系统的社会效益. 计算结果表明: 减小地震预警盲区范围对提高地震预警系统的效能非常关键; 地震预警系统的建设和台网布局应重点考虑布设区域的人口密度、 经济情况及地震发生概率. 相似文献
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在地震早期预警系统中具破坏性地震震中的确定速度十分重要.本文提出了地震发生后根据1个、2个、3个台站P波到时记录进行动态、近实时确定地震发生区域、线区间和震中位置的方法.方法充分考虑了地震触发台站和非触发台站分布与地震波传播规律的一致性和差异性特征,提高了震中定位结果的精度.对由79个台站组成的山东虚拟测震台网2009-2010年期间记录的425次网内地震进行了快速定位,结果表明对发生在网内的地震可在要求时间内给出比较准确的震中位置,可满足预警地震速报时效性和精度的双重要求. 相似文献
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结合福建地区地震预警系统的运行情况和处理能力, 利用日本KiK-net台网和福建地震台网记录的天然地震事件和人工爆破事件实测数据, 探讨了Pd-τc相容性检验方法在触发事件类型实时判别中应用的可行性． 结果表明, Pd-τc相容性检验方法能够较好地区分大震级地方震与误触发事件, 也能对远震事件进行粗略判别, 但对于小震级地方震和人工爆破事件则无法有效判别． 随后, 以Pd-τc相容性检验结果为基础, 本文设定强度参数Pd=10-3 cm为界线, 即可从众多触发事件中甄选出可能产生破坏的大震级地方震事件． 本文方法有助于提高触发事件类型判别结果的可靠性、 预警系统的处理效率和系统产出信息的准确度． 相似文献
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利用地震预警系统对中国台湾地区地震进行速报,与传统地震告警软件对比后发现,预警系统能够在较短时间内得出地震三要素并告警,可为地震速报人员争取较长速报用时。总结了地震速报过程中需要注意的若干细节问题。 相似文献
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Finite Fault Modeling in a Tsunami Warning Center Context 总被引：1，自引：0，他引：1
The US NOAA/NWS tsunami warning centers have relied on earthquake location and depth, and scalar measures of earthquake size and slowness to assess the potential for the generation of a destructive tsunami by an earthquake. Recent earthquakes, such as Peru 2001, Sumatra 2004 and the Java 2006, manifest some of the difficulties the warning centers face as they try to cope with unusual earthquakes. We have undertaken a study of a simple teleseismic waveform inverse model and applied it to the earthquakes of June 23, 2001 in Peru and of July 17, 2006 in Java. Synthetic numerical experiments suggest that the most salient features of the rupture history of an earthquake can be recovered. Furthermore the calculations can be conducted quickly enough to be useful in a warning center context. We have applied our technique to the Peru 2001 and recent Java 2006 earthquakes. Our overall results are consistent with those obtained from other studies. The results show why the Peru event initially looked slow to the US tsunami warning centers and that the Java event is a truly slow or tsunami earthquake. Clearly, the warning centers stand to benefit from an increased understanding of the earthquakes they monitor. Furthermore, better knowledge of the slip distribution along a fault will improve tsunami wave-height forecasts. 相似文献
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利用自动经验基线校正方法,分析日本2008年岩手-宫城内陆Mw6.9地震震中周围密集强震动观测台网资料,快速解算出了同震位移场分布,并据此反演了震源滑动模型.经与GPS结果比较,两种不同方法给出的同震位移幅值、方向和总体分布特征较为接近.基于相同断层面参数反演的震源模型空间展布形态、主要滑动范围、平均和最大滑动量、滑动方向以及由模型计算的矩震级等均吻合较好,从而验证了方法的可行性.讨论了自动经验基线校正方法尚存在的问题和不足,为今后利用强震资料快速解算Mw6-7级及以上地震的同震位移场并反演震源滑动分布提供参考. 相似文献
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日本地震预警系统发展历程 总被引：1，自引：0，他引：1
地震预警（EEW）或实时地震预警系统是指,几秒内检测到临近区域可能发生的强烈地震后,对本地提供预警信息的系统。地震预警的目标是,通过相应决策让人们能够在多种环境中保护自己,并减轻与地震相关的次生灾害。本文详细介绍了地震预警系统在日本的发展历程,指出预警信息已不再局限于向高级用户和公众用户进行发布,私人定制用户已成为预警信息发布的重要需求。未来地震预警技术的发展,特别是实时断层源成像识别技术,对改善预警系统并快速识别震源参数具有重要意义。 相似文献
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选取2009—2014年华北—东北地区发生的12次中等地震,对该区8个地磁台站记录的地磁Z分量日变幅进行小波分析及合成计算,与日本海沟同期发生的12次M≥6.5强震进行关联性分析,发现日本强震对中国华北—东北地区中等地震活动具有连带作用,表现在:①日本强震发生前后,华北或东北地区均有M4—5地震出现,频次一般为1—3,间隔几天至5个月左右;②2011年3月10日日本M9.1地震后,华北、东北地区中等地震震级有所升高,其中东北地区由M4升至M5,距日本最近的中俄交界甚至出现M6.1地震,华北地区唐山老震区出现1次M4.8地震,震级接近5;③每次日本强震出现后几天至2个月内,8个地磁台地磁Z分量小波细节6阶合成曲线值均出现2—6个月高值异常,但幅度大小与强震震级无明显规律可循,而华北或东北地区中等地震一般在异常高值出现前后低值附近发生。 相似文献
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近场P波频谱分布及震级确定方法 总被引：1，自引：0，他引：1
通过研究国内12个4~7级地震的近场P波前3秒加速度波形记录的频谱分布, 我们发现, 对于较大的地震, 近场通常接收到的低频信息比较稳定, 尤其是1 Hz以下的信号。 通过对3秒初至P波震相加速度记录的低频窄带滤波及对传统震级公式的改造, 我们得到了4个低频段的震级计算公式M1, M2, M3, M4及预警震级计算结果Mn。 将其应用到日本13个4~7级的地震中, 并对比目前主流Pd震级计算方法, 我们的结果离散度与可靠性更好。 因此, 可认为我们得到的震级公式是较可靠的一种估算近场震级的方法, 并且可以应用到地震预警中。 相似文献