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501.
The development of reliable, accessible, and transparent earthquake early warning systems (EEWSs) for disaster reduction have been given increased priority at local, national, and international levels. Accurately quantifying the social and economic benefits accrued to households and businesses from EEWSs are a challenging and difficult task. In this paper, the Contingent Valuation Method (CVM) is used to evaluate the benefits of a hypothetical EEWS to the citizens of Tehran Metropolitan. This study clarifies public willingness to pay (WTP) for EEWS in Tehran, and the dominant factors involved in WTP through a CVM analysis. The survey, completed by more than 504 households, showed that on average households are willing to pay 367,471 Rials (~38 US$) per month for the hypothetical EEWS. Those willing to pay the most for EEWS are households, which currently possess a fire alarm. Also the more educated the respondents and the more children the respondents have, the more willing they are to pay for EEWS. These results could be used by policy makers and technology firms in order to determine the optimal investments in early warning systems for earthquake disaster reduction.  相似文献   
502.
为了解决当前我国地铁施工过程的安全预警问题,构建因子分析与BP神经网络相结合的地铁施工安全预警模型。在分析地铁施工安全预警指标的基础上,采用SPSS因子分析法对调查数据进行降维,采用Visual Basic 6.0软件编写BP网络程序,并通过工程实际数据实现模型的训练及检测。研究结果表明,通过因子分析能使BP网络的输入数据从37个减少至7个,经因子分析降维后的收敛速度和计算精度均高于未经因子分析的神经网络,且误差均在10%以内。通过因子分析与BP神经网络相结合构建的耦合模型识别地铁施工过程中的不安全因素,进而有针对性地完善地铁施工的相关预警技术。  相似文献   
503.
为提高施工期土石坝沉降安全性,研究其具有复杂非线性特征的施工期沉降规律和相应的预警标准。基于国内某在建高土石坝的沉降数据,采用R/S法分析坝体不同高程测点、同高程测点和同测点不同时期沉降数据的Hurst指数及分形维数,提出评价坝体施工期沉降安全性的预警标准。结果表明:各测点的Hurst指数最小值为0.763,坝内各处沉降仍处于快速增长阶段;坝体下部比上部、中部比下游堆石区沉降能更快趋于稳定,且坝体下部的沉降速率已经渐趋平缓。  相似文献   
504.
基于雷电监测预警技术,提出了一种新型的加油站防雷预案执行方案,解决了现有的应急预案无准确执行依据的问题。方案引入近几年成熟的电场监测和雷电定位技术,对加油站周边地区的电场和雷击情况进行实时监测,并基于监测数据和加油站业务特点建立数学模型,结合先进的物联网和云计算技术,在雷电发生前获得高精度的短时雷电预警信息,在此基础上设计了加油站防雷预案执行方案,最后对方案的应用效果进行了分析。  相似文献   
505.
长江,黄淮流域近期特大洪水预警和防洪形势   总被引:13,自引:1,他引:12  
根据太阳黑子活动和长江,黄淮流域1840 ̄1994年历史和实测的洪水资料,推断在1997年及其前后,长江,黄淮流域很有可能出现一次特大的洪水。同时指出,目前长江、淮河、黄河的防洪形势不容乐观,必须及早采取对策,确保人民生命和财产的安全。  相似文献   
506.
Jeremy Shoham 《Disasters》1987,11(4):282-285
A major area of investment in data collection in developing countries has been that of nutritional surveillance and monitoring. From recent debate it is clear that there is currently no consensus on the potential role of nutritional status as an early warning indicator. The author presents a synthesis of the broad spectrum of views on the role nutritional surveillance could or should have in early warning. Conceptual problems and technical difficulties are reviewed in the light of recent experiences in Africa and Asia. The author raises a number of issues for future discussion in this ongoing debate.  相似文献   
507.
CFD方法对突发性化学事故中危险物质泄漏范围的确定   总被引:1,自引:0,他引:1  
简要分析了目前国内主要用于预测易燃易爆(有毒)物质发生泄漏事故后浓度扩散范围的计算方法。并介绍了国际上比较成熟的计算流体力学相关软件的数学模型及特点和边界条件的设置。针对液氨发生泄漏后氨气在一定大气环境条件下扩散的过程和特征,建立了相应的数学模型并设置了边界条件,通过数值计算得到氨气在水平方向风速环境下在三维空间内浓度分布规律。通过分析氨气扩散后爆炸浓度下限范围,探讨了如何设置警戒区的方法。最后分析了将计算流体力学方法应用于确定易燃易爆(有毒)物质泄漏后浓度范围的前景与不足。  相似文献   
508.
On 1 March 1997, powerful tornadoes touched down in Arkansas (USA) on a Saturday afternoon. Twenty-six fatalities and 400 non-fatal injuries were reported. We performed a population-based cross-sectional study to determine factors associated with appropriate responses to tornado warnings. Of 146 survey participants, 140 (96 per cent) knew the difference between 'tornado watch' and 'tornado warning' and were aware of when the warning was announced. Of those 140 participants, 64 (45.7 per cent) responded to the warning by seeking shelter, and 58 (90.6 per cent) of those 64 acted within five minutes of hearing the warning. Four factors were positively associated with those seeking shelter: having graduated from high school (OR = 4.2, 95 per cent CI = 1.1-15.5); having a basement in one's house (OR = 3.8, 95 per cent exact CI = 1.1-17.1); hearing a siren (OR = 4.4, 95 per cent CI = 1.3-18.9); and having prepared a household plan of response when tornadoes occur (OR = 2.6, 95 per cent CI = 1.1-6.3). On the basis of these findings, we recommend: first, that people who live in tornadoprone areas have a personal plan of action to help them respond immediately to warnings; second, public-health education officials in areas with frequent tornadic activity should do more to educate the public about what they can do to protect themselves from a tornado; and third, that emergency-management officials planning protection measures for vulnerable communities should consider that most people have limited time (our study documented five minutes) in which to respond to a tornado warning. Thus, shelters in tornado-prone areas should be quickly accessible by residents.  相似文献   
509.
Flood warning systems offer a large potential for reducing human losses and property damage in flood-prone regions. This article illustrates why official organized systems should not be relied on completely in either developing or developed societies. It then discusses an indigenous flood warning system in a rural area of Eastern India, its value, and its importance in providing an alternative means of detecting, interpreting, and relaying flood warning information to the ultimate users of this information, i.e., those populations most at risk from floods.The National Center for Atmospheric Research is operated by the University Corporation for Atmospheric Research and is sponsored by the National Science Foundation.  相似文献   
510.
我国危险废物应急管理工作基础较为薄弱。如何快速提升和完善危险废物污染预警和应急响应能力已逐渐成为我国危险废物管理领域研究的重要内容。本文立足我国危险废物污染预警及突发事件应急响应能力建设现状,探讨上海市危险废物污染预警及突发事件应急响应平台的建设内容,建立了典型示范基地以验证平台的实际应用价值,以期为我国其他地区开展险废物污染预警及突发事件应急响应平台建设提供借鉴,为政府环境应急管理系统构建提供技术支持。  相似文献   
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