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821.
ABSTRACT The flooding conditions in the basin of the Red River of the North are reviewed in terms of the accuracy of the flood forecasts and the response of both the floodplain occupants and government agencies to these forecasts. The flood prediction methods in Canada and the United States are compared. The accuracy of these prediction measures for the major floods in recent history is reviewed. The differences between the way in which the American and Canadian authorities approach the flood emergencies are outlined. The accuracy of the forecasts are plotted against a number of parameters which reflect the efficiency of the flood fighting measures initiated by those flood forecasts. The significant features of these plots are discussed.  相似文献   
822.
MS SQL SERVER复制技术在地震前兆数据集成中的应用   总被引:1,自引:0,他引:1  
基于WINDOWS NT 网络操作系统的MS SQL SERVER复制环境,分析并探讨了SQL SERVER复制技术、 复制模块的参数设置及其在地震前兆数据集成中的应用。 通过实例说明了SQL SERVER复制技术在地震前兆数据集成中应用的可行性。 同时,对复制过程中常出现的事务日志空间问题进行了剖析,并提出了解决办法。 分析结果表明,应用SQL SERVER复制技术进行数据交换、 共享及应用是较为有效的,而且也是可行的。  相似文献   
823.
通过对基于Browser Server体系的Web技术的分析与实践 ,开发了一种在分布式计算环境下 ,基于动态网页的数据库查询系统的方法 ,并介绍了在SGIIRIX 6 .5系统下对之的实现过程以及所采用的开发工具等。  相似文献   
824.
研究分析了高邮地磁台1980~2001年观测资料的加卸载响应比异常与江苏及邻近地区ML5.0以上地震之间的关系,提出了适用于高邮地磁台的地震分析预报参数,并对其内检预报效能进行了评价。  相似文献   
825.
模糊综合评价在脱硫技术优选中的应用   总被引:4,自引:0,他引:4  
基于模糊数学的基本原理,采用模糊矩阵和专家打分法(德尔菲法)相结合的方法,通过模糊综合评价来进行脱硫方案的优选。实例计算表明,此方法在脱硫技术优选中是可行的。  相似文献   
826.
突发性环境污染事故风险管理进展   总被引:1,自引:0,他引:1  
在介绍突发性环境污染事故的概念、类型与特性的基础上,综述了近年来国内外风险管理的进展。要对突发性环境污染事故进行风险管理,需要有组织的风险管理体系和风险管理计划。风险管理计划应当包括危害的风险评价、预防和应急反应三部分内容。文中详细阐述了突发性环境污染事故的预防、应急处理与对策、善后处理与影响评价的主要内容和方法。  相似文献   
827.
Objectives: The majority of existing investigations on attention, aging, and driving have focused on the negative impacts of age-related declines in attention on hazard detection and driver performance. However, driving skills and behavioral compensation may accommodate for the negative effects that age-related attentional decline places on driving performance. In this study, we examined an important question that had been largely neglected in the literature linking attention, aging, and driving: can top-down factors such as behavioral compensation, specifically adaptive response criteria, accommodate the negative impacts from age-related attention declines on hazard detection during driving?

Methods: In the experiment, we used the Drive Aware Task, a task combining the driving context with well-controlled laboratory procedures measuring attention. We compared younger (n = 16, age 21–30) and older (n = 21, age 65–79) drivers on their attentional processing of hazards in driving scenes, indexed by percentage of correct responses and reaction time of hazard detection, as well as sensitivity and response criteria using signal detection analysis.

Results: Older drivers, in general, were less accurate and slower on the task than younger drivers. However, results from this experiment revealed that older, but not younger, drivers adapted their response criteria when the traffic condition changed in the driving scenes. When there was more traffic in the driving scene, older drivers became more liberal in their responses, meaning that they were more likely to report that a driving hazard was detected.

Conclusions: Older drivers adopt compensatory strategies for hazard detection during driving. Our findings showed that, in the driving context, even at an older age our attentional functions are still adaptive according to environmental conditions. This leads to considerations on potential training methods to promote adaptive strategies that may help older drivers maintain performance in road hazard detection.  相似文献   
828.
大坝安全监测的现状与发展趋势   总被引:1,自引:0,他引:1  
阐述了大坝安全监测的内涵及意义。分别从大坝安全监测的内容、思维、分析方法和技术手段四个方面介绍了大坝安全监测的现状和发展趋势,并指出自动化、数字化、一体化、效益化是大坝安全监测的最终发展方向。  相似文献   
829.
首先简单介绍了离心模型试验技术的发展状况,然后探讨了其在环境岩土工程中的应用,研究了模型和原型的相似规律,提出了环境岩土工程离心模型试验的发展方向.  相似文献   
830.
Following the severe flood events of 1998 and 2000, the United Kingdom's Environment Agency prioritised the need to increase public flood risk awareness. Drawing on data collected during research undertaken for the Environment Agency, this paper contributes to understanding of one aspect of flood awareness: people's recognition that their property is in an area that is potentially at risk of flooding. Quantitative analyses indicate that class is the most influential factor in predicting flood risk awareness, followed by flood experience and length of time in residence. There are also significant area differences. Our qualitative work explores how those defined as 'at risk' account for their lack of awareness or concern about their risk status. We conclude that the problem is often not simply a lack of awareness, but rather, assessments of local risk based on experience that underestimate the impact of rare or extreme events. We underline the importance of engaging with local perspectives on risk and making local people part of 'awareness-raising' processes.  相似文献   
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