首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
本文发展了一种加权平均方法,用于综合考虑地震危险性分析中的专家意见。其中假定接近综合结果的专家意见具有的权系数较大,这样可以合理反映专家意见的一致性与差异性,另外,利用随机加权方法估计综合结果及权系数的不确定性,给出其统计特征量。  相似文献   

2.
本文的主要目的是为工程地震危险性分析提供一种考虑地震发生空间不均匀性的概率模型。采用伯努利试验模型描述了在一给定震源区内地震发生位置的不确定性,并利用贝叶斯方法将观测数据与专家的主观判断相结合给出了地震发生概率的均衡估计。同时也给出了综合专家主观意见的方法和计算场地烈度超过概率的方法。从而为在工程地震危险性分析中充分反映地震地质学家和地球物理学家关于地震中长期预报的意见提供了一种定量的方法。  相似文献   

3.
本论文介绍和总结了目前桥梁结构可靠度问题的研究现状,建立了桥梁结构在随机地震荷载作用下可靠度分析的模型,讨论了桥梁结构在地震力作用下危险截面的选取问题,解决了功能函数的复杂性和难于求导的问题,利用遗传算法对桥梁结构进行了可靠性分析,并与JC算法进行了比较研究。最后,通过算例说明了本文方法的可行性和正确性,本方法可为桥梁结构地震可靠性分析和加固提供理论依据和参考意见。  相似文献   

4.
为了更好地评价和比较城市的地震灾害风险,建立了基于熵权的新的地震灾害风险指数(EDRI)模型。在地震灾害风险指数的建立过程中,根据信息熵理论计算熵权,采用熵权与专家意见相结合的方法确定风险指数的综合权重,从而使模型权重的确定更加合理。通过算例分析,新的计算模型可以降低城市地震灾害风险指数对专家主观意见的依赖,从而使计算变得更加客观、科学。  相似文献   

5.
地震危险性不确定性分析中专家意见的合理综合   总被引:2,自引:0,他引:2  
首先回顾了不确定性分析中常用的专家意见综合方法。然后在此基础上,提出了一新的简便易行的综合方法,并利用实例计算比较了三种综合方法的结果差异。所提出的方法在地震危险性不确定性分析专家意见的合理综合中具有较为实用的价值。  相似文献   

6.
多层砌体房屋地震现场安全性鉴定子系统的研制与开发   总被引:2,自引:1,他引:1  
本文利用模糊综合评判原理研究了多层砌体房屋地震现场安全性鉴定方法,并以此为基础研制了多层砌体房屋地震现场安全性鉴定子系统。本文将该子系统运用到两个实际问题中,所得结论与专家基于经验的现场鉴定相吻合,初步验证了系统分析模块的可靠性。  相似文献   

7.
基于MSC.Marc二次开发的土体静力和地震非线性分析方法   总被引:2,自引:0,他引:2  
本文在MSC.M arc提供良好的用户二次开发环境下,利用用户使用的应用编程接口USER SUB.HYPELA,添加了多层土的静力Duncan-Chang本构关系模型和动力等效线性化本构关系模型,并通过两个算例验证了本文二次开发的可靠性。  相似文献   

8.
基于动力可靠性分析的滑移隔震体系的优化设计   总被引:10,自引:2,他引:8  
本文探讨了滑移隔震体系在零均值高斯白噪声地震作用下的优化设计问题,首先利用编译等效线性化方法并按首次超超损坏泊松过程模型的双壁问题得到质点的滑移可靠性函数,然后采用拉格朗日乘子法进行了该滑移隔震体系基于动力可靠性分析的优化设计。  相似文献   

9.
地震危险性与核电厂密闭可靠性的评价方法   总被引:1,自引:0,他引:1  
本文就考虑地震危险性时,核电厂安全壳的防泄露可靠性的评价方法进行了理论研究,探讨了地震模型问题中的参数确定的一些方面,给出了可靠性评价的总体思路、分析方法及具体步骤,确定了要考虑的不定参数及其描述,并进而利用概率断裂力学推导出可靠性计算的一般公式。  相似文献   

10.
本文提供了一种弥补震害预测时历史地震资料不足的方法,给出了构造离散型多因素预测矩阵的模型。利用本文提供的方法进行预测所得结果较易进行可靠性分析。实践证明,本文所介绍的建立在近似推理理论基础上的方法基本上满足一般震害预测的需要。  相似文献   

11.
利用“专家系统”的思想对每一地震前兆异常事件进行了综合评估,以每一异常的最可能发震时间计算发震概率,利用各类地震前兆异常群体信息熵研究了系统熵值与地震场,源兆的关系,分析了1976年唐山7.8级地震前各类地震前兆异常的时空分布特征,然后以唐山为中心在空间上划分三个区,近区,中间区和远区,分别计算了三个区各类地震前兆异常信息熵的时间演化值,分析了震前这种信息熵的场,源兆特征,震中近区的信息熵值要比中  相似文献   

12.
This paper is the follow-up of an earlier paper by the same author on the calculation of standard-graphs for horizontally stratified subsoils. The method which was developed in that earlier paper was destined for handwork; it was laid down in master-tables. The present paper deals with the presentation of similar methods to the computer expert in purely mathematical denotation. Two different denotations are described for the calculation of the image pole strengths involved. The first denotation is an improved version of Watsons formulae; it gives the total strengths. The second denotation preserves the character of successive approximations as described in the previous paper. Both denotations have been worked out until a six layer resistivity profile, but actually there is no limitation to the number of layers. There is no restriction to the resistivities of any layer. The only condition is now that all interface depths must be integers. This paper is followed by a paper on the relevant computer program by Argelo in this same issue  相似文献   

13.
地震前红外异常的基本特征与成因机理   总被引:17,自引:3,他引:14       下载免费PDF全文
通过分析发生在中国及相邻地区的40多次地震的卫星热红外图像,总结了卫星红外临震异常的基本特征。对有关异常成因机理的诸家观点进行了阐述,提出了作的倾向性意见。一般情况下Ms>5地震前均有较清晰的红外临震异常显示,低空大气-地面增温幅度显,并表现出突发性和阶段性特征。异常面积与震级的大上呈一定程度的正相关。作倾向于认为,临震大气静电异常对大气的极化作用是产生热红外异常的主要原因,异常大气的温室效应也是不可忽视的因素。  相似文献   

14.
 To preserve biodiversity over centuries, ecosystem management will need to be accepted and practiced by individuals from a broad spectrum of society's strata. Also, management decisions will need to be based on reliable judgments of the cause and effect relationships that govern an ecosystem's dynamics. This article describes an extant, web-based ecosystem management system (EMS) that allows (a) wide participation in ecosystem assessment and policy impact predictions, (b) convenient construction of probabilistic models of ecosystem processes through an influence diagram, and (c) automatic creation of ecosystem assessment reports. For illustration, the system is used to first model the cheetah population in Kenya, and then to assess the impact on this population of different management options. The influence diagram used herein extends standard influence diagram theory to allow representation of variables governed by stochastic differential equations, birth–death processes, and other nongaussian, continuous probability distributions. For many ecosystems, data sets on ecosystem health indicators can be incomplete, small, and contain unknown measurement errors. Some amount of knowledge of an ecosystem's dynamics however, may exist in the form of expert opinion derived from ecological theory. The proposed EMS uses a nonbayesian parameter estimation method, called consistency analysis that finds parameter estimates such that the fitted ecosystem model is as faithful as possible to both the available data and the collected body of expert opinion. For illustration, consistency analysis is used to estimate the cheetah viability influence diagram using all known cheetah surveys in the country of Kenya plus current understanding of factors such as habitat and prey availability that affect cheetah population dynamics.  相似文献   

15.
高层钢筋混凝土结构抗震选型的模糊专家系统   总被引:13,自引:2,他引:13  
本文在专家调查和文献资料收集事理的基础上,建立了高层钢筋混凝土结构抗震选型的影响因素。因素关系及其模糊量化的知识表示方法;针对结构选型因素的层次性,提出了层因素逐级综合的模糊推理方法;在开发工具C-ADVISOR上具体建造了此类结构抗震选型的专家系统。  相似文献   

16.
罗灼礼  程万正 《地震学报》1981,3(4):351-360
本文推导了各类点源和线源(压性、张性、压扭性、张扭性、单力偶和双力偶)的理论地震位移场公式, 讨论了板内地震的震源力学性质.根据实测地震位移场、建筑物破坏和倒塌的优势方向等近场资料与理论结果对比, 作者认为, 1966年邢台地震震源机制符合于张性断裂的模型;1966年东川地震震源机制符合于压扭性断裂的模型.根据理论公式和实际位移资料, 给出了邢台地震的地震矩 M0为6.51026达因厘米, 应力降△为39巴.最后指出大地震的震源力学机制反映了该区域长期构造应力作用的状态, 认为双力偶(剪切位错)不一定是板内地震震源机制的最合适的、唯一的模型.   相似文献   

17.
政务新媒体是解决政府信息公开、应对舆情和提升服务能力的一把金钥匙,建立媒体矩阵是提升地震系统新媒体整体覆盖力、传播力、影响力、公信力的有益尝试,是解决地震事件应对过程中信息快速发布、快速辟谣的有效方式。作者通过对地震事件新媒体矩阵现状、发展特征、存在问题进行分析,提出发展趋势判断及建议。  相似文献   

18.
地震事件新媒体矩阵传播特征分析   总被引:1,自引:0,他引:1  
政务新媒体是解决政府信息公开、应对舆情和提升服务能力的一把金钥匙,建立媒体矩阵是提升地震系统新媒体整体覆盖力、传播力、影响力、公信力的有益尝试,是解决地震事件应对过程中信息快速发布、快速辟谣的有效方式。作者通过对地震事件新媒体矩阵现状、发展特征、存在问题进行分析,提出发展趋势判断及建议。  相似文献   

19.
Habitat Suitability (HS) models have been extensively used by conservation planners to estimate the spatial distribution of threatened species and of species of commercial interest. In this work we compare three HS models for the estimation of commercial yield potential and the identification of suitable sites for Tapes philippinarum rearing in the Sacca di Goro lagoon (Italy) on the basis of six environmental factors. The habitat suitability index (HSI) is based on expert opinion while the habitat suitability conditional (HSC) is calibrated on observational data. The habitat suitability mixed (HSM) model is a two-part model combining expert knowledge and regression analysis: the first component of the model uses logistic regression to identify the areas in which clams are likely to be present; the second part applies the same parameter-specific suitability functions of the HSI model only in the areas previously identified as productive by the logistic component.The HS models were validated on an independent data set and estimates of potential yield of the Goro lagoon were compared. The effectiveness of the three approaches is then discussed in terms of predicted yield and identification of suitable sites for farming.  相似文献   

20.
《Marine pollution bulletin》2008,56(10-12):579-590
Habitat Suitability (HS) models have been extensively used by conservation planners to estimate the spatial distribution of threatened species and of species of commercial interest. In this work we compare three HS models for the estimation of commercial yield potential and the identification of suitable sites for Tapes philippinarum rearing in the Sacca di Goro lagoon (Italy) on the basis of six environmental factors. The habitat suitability index (HSI) is based on expert opinion while the habitat suitability conditional (HSC) is calibrated on observational data. The habitat suitability mixed (HSM) model is a two-part model combining expert knowledge and regression analysis: the first component of the model uses logistic regression to identify the areas in which clams are likely to be present; the second part applies the same parameter-specific suitability functions of the HSI model only in the areas previously identified as productive by the logistic component.The HS models were validated on an independent data set and estimates of potential yield of the Goro lagoon were compared. The effectiveness of the three approaches is then discussed in terms of predicted yield and identification of suitable sites for farming.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号