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1.
地震现象的新观点   总被引:1,自引:0,他引:1  
本文综述断裂和碎形理论的最新进展,以分形的观点解释地震学经验公式,提出了地震作为自组织临界现象(SOC)的观点。地震的发生是地壳中的能量耗散过程,而地壳构造能量连续地得到补给,地壳的自组织行为达到临界状态,时间上和空间上的分形结构就自然呈现出来。众所周知,在地震中幂次律关系即是地壳临界状态的表述。本文还提出了一个地震的SOC模型,用以解释古登堡-里克特公式,大森的余震公式以及震源的分形分布。地震现  相似文献   

2.
细胞自动机的多重分形特征和动力学根源   总被引:2,自引:0,他引:2       下载免费PDF全文
用大量弹簧滑块组成的模型可以模拟地震的复杂性,本文以细胞自动机(CA)为数学工具,结合地震学和岩石力学的结果,考虑了能量的输入和损耗,进行了地震事件的数字模拟。对模型中输出的"地震"事件进行了时间和空间的多分形分析,并对自组织临界(SOC)状态进行了讨论,进而得到事件至少在时间域里的分布呈现出层次结构,符合自相似特征。本文的CA模型属于确定性的混沌系统,而对于处在SOC状态下的大量事件的频度和大小的统计与G-R指数律很好地吻合。结果表明,虽然自组织(SO)可能是更准确的地震表征,但SOC仍然是研究地震现象的很好的模式。  相似文献   

3.
1932年昌马地震构造力学特征探讨郭万武,张范民,邢成起,温增平(国家地震局兰州地震研究所,兰州)DISCUSSIONONTHETECTONOMECHANICFEATURESOF1932CHANGMAEARTHQUAKEMs7.6¥GuoWanwu;...  相似文献   

4.
吴忠良 《中国地震》1998,14(4):9-10
目前国际上围绕地震预测问题的争论,很大程度上与地震的自组织临界性模型有关。根据地震SOC模型,地震预测被认为是不可能的。事实上,这是一个误解这个误解又是关于地震的SOC模型的诸多误解中的一个。在地震的SOC模型中,地震的能量-频度关系具有重要的地位。  相似文献   

5.
目的是探讨标记乳糖基白蛋白的超顺磁性氧化铁粒子(LAC-HSA-SPIO)作为配体与肝细胞膜去唾液酸糖蛋白受体(ASG)特异性结合可能性;评价LAC-HSA-SPIO增强磁共振受体成像对大鼠微小肝癌灶的显示能力。方法:将Fe3+Fe2+混合液与LAC-HSA在碱性条件下制备出LAO-HSA-SPIO;应用 二乙基亚硝酸胺建立大鼠肝癌模型;电镜及Perls(普鲁士蓝)染色,观察LAC-HSA-SPIO在肝组织的颁;并比较LAC-HSA-SPIO增强前后大鼠肝癌的显示情况。得到结果是(1)Perls染色证实有LAC-HSA-SPIO分布到肝细胞浆内;电镜下也显示肝细胞膜表面及胞浆内有电子致密SPIO粒子分布;(2)注射小剂量LAC-HSA-SPIO可观察到明显明显肝脏强化效果,大鼠肝癌检出率由平扫36.8%(7/19)提高到78%(15/19,P<001)。结论:LAC-HSA-SPIO是一种新型的具有肝细胞ASG受体靶向性显影剂,对提高肝脏微小瘤灶检出率有章要价值。  相似文献   

6.
新一代CDSN台站的地震信息管理,采用ORACLE关系数据库系统。该系统主要由ORACLE的核心,SQL*PLUS接口及各种实用程序组成(图1)。台站SUN工作站系统配置的ARS软件,是分析处理数字化地震资料的较为理想的应用软件。支持该软件的就是OR...  相似文献   

7.
介绍了IRIS的研究计划和项目:①全球地震台网(GSN);②大隅岩石圈台阵地震研究计划(PASSCAL);③数据管理中心(DMC)全球数据管理系统(DMS);④教育与扩展计划(E&O);⑤海洋地夺台网(OSN)。概述了IRIS跨世纪规划和项目研究的最新进展情况。  相似文献   

8.
依据实验室高温条件下获得的岩石物理特性建立乌兹别克地震活动区域地壳岩石物理模型巴卡耶夫M.Kh,阿布诺基莫夫A.Kh(乌兹别克斯坦科学院地震学研究所,塔什干)PETROPHYSICAIMODELSOFTHEEARTH'SCRUSTINSEISMICA...  相似文献   

9.
精密可控常时震源系统(ACROSS)的初步实验   总被引:4,自引:1,他引:4  
地震是重大自然灾害之一 ,长期以来 ,人们不断地发展各种地震观测手段 ,探索地震预报之路。精密可控常时震源系统ACROSS(AccuratelyControlledRoutinelyOperatedSignalSys tem)是国际上 2 0世纪 90年代以来发展起来的一种新型可控震源技术。目的是通过产生精密可控的地震波和采用先进的观测与处理技术监测地震发生区域地层物理状态的微小变化。ACROSS震源与通常的爆破震源相比 ,有如下主要特点 :( 1 )ACROSS震源产生的是单一弹性波 ,从能量的角度讲 ,机械波的能量效率…  相似文献   

10.
国际地震学与地球内部物理学协会亚洲区域大会将在我国唐山举行由亚洲地震委员会(ASC)、中国国家地震局主办,由国际地震学与地球内部物理学协会(IASPEI)、唐山市政府、国际岩石国计划(ILP)、联全国教科文组织(UNESCO)、中国国家自然科学基金委...  相似文献   

11.
12.
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.  相似文献   

13.
14.
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  相似文献   

15.
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.  相似文献   

16.
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  相似文献   

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Copyright     
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19.
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  相似文献   

20.
Dissolved total carbohydrates (DTCH), dissolved free monosaccharides (DFMS), dissolved organic carbon (DOC), biodegradable DOC (BDOC), and humic substances (HS) were measured in White Clay Creek (WCC), a stream in southeastern Pennsylvania Piedmont, USA. Samples were collected over different seasons and under baseflow and stormflow conditions. DOC concentrations ranged from 1.0 to 12.8 mg/L C with the highest concentrations associated with stormflows. Carbohydrates ranged from 0.42 to 12.4 μM and accounted for 2.9 to 12.7% of the DOC. Humic substances represented the major DOC fraction, accounting for 55 to 72% of the DOC pool under all flow conditions. The humic fraction had a lower carbohydrate content (4.4%) than the non-humic fraction of DOC (7.2%). Stormflow DOC was enriched in carbohydrates relative to baseflow DOC, but the percentage of humic-C changed little. Carbohydrates were primarily present as dissolved polysaccharides (55%), but a significant fraction was bound to humic substances (40%), while a small proportion was present as monosaccharides (5%). The major monosaccharides in stream water, listed in order of decreasing concentration, included glucose, galactose, rhamnose, xylose, arabinose, mannose, and fucose. On average (30.6 ± 7.4)% (n = 44) of the stream water DOC was biodegradable, and carbohydrates accounted for 9.9 to 17.7% of the BDOC.  相似文献   

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