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491.
应用环境预警系统,对TEDA1998-2001年环境质量进行分析、评估与预测,通过评分得到TEDA水环境、大气环境、噪声环境和整体环境的预警结果,对预警结果进行分析表明:TEDA综合环境质量1998年出现较差状态预警,1999年、2000年和2001年综合环境质量均未出现警值,这说明天津经济开发区环境状况朝着良好的方向发展。 相似文献
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494.
One of the major changes in flash-flood mitigation in the past decade is the number of communities that have implemented warning systems. The authors conducted a survey of 18 early-warning systems in the United States developed by communities or regions to provide protection against flash floods or dam failures. Problems revealed by the study included the following: equipment malfunctions, inadequate maintenance funding, inconsistent levels of protection and expenditure, inconsistent levels of expectations and formalization, varying levels of local commitment to the systems, underemphasis on response capability, and a tendency to over-rely on warning systems. The study also revealed some unanticipated benefits experienced by the survey communities: the warning systems serve as valuable data collection tools, a great deal of interagency cooperation has been demonstrated, and warning systems offer increased alternatives to structural modification projects. The interjurisdictional nature of drainage basins, the evolving roles of the various federal agencies involved in flood mitigation, and the lack of governmental standards of operations for flood warning systems are issues that must be considered as communities make decisions regarding the adoption of warning systems. The record on these systems is too short for a precise assessment of how successful they are; however, results of the study indicate that if the goal of reducing loss of life and property from flooding is to be achieved, warning systems must be only one part of a comprehensive flood loss reduction program. 相似文献
495.
为研究荧光示踪剂在包气带土壤中的迁移-吸附特性,指导填埋场渗漏检测过程的示踪剂选择、投加和采样.采用土柱实验、参数反演手段,研究3种典型荧光示踪剂在包气带中的吸附、滞后和穿透规律,确定其迁移表征方法、表征参数和最佳模型.结果表明:在土壤有机碳相对较高和较低时,分别可用非线性平衡和线性平衡模型准确拟合罗丹明B在其中的穿透数据,而非线性平衡模型同时准确拟合了荧光素和荧光素钠在两种有机碳土壤中的穿透数据.基于最优反演模型,在低有机碳土壤中示踪剂迁移参数为:罗丹明B、荧光素和荧光素钠的分配系数分别为84.99,1.80,1.48cm3/g,滞后因子分别为393.27,8.18,7.81,吸附容量分别为6.14×10-3,0.15×10-3,0.14×10-3mg/g,均出现罗丹明B>荧光素>荧光素钠的顺序.荧光素钠在包气带中迁移时固相吸附浓度最小、迁移速率最快、吸附消耗量最小,建议在进行填埋场渗漏示踪中选用. 相似文献
496.
Thomas Lilley Toni Laaksonen Otso Huitu Samuli Helle 《Behavioral ecology and sociobiology》2009,63(10):1539-1547
The ratio of second-to-fourth digit length (2D/4D) has been suggested to be a useful adult age marker of intrauterine exposure
to steroids because it should be sexually dimorphic and fixed already in utero. Numerous studies mainly on humans have supported
this conclusion, but it is yet unclear how well this applies to other vertebrates. This information would be especially valuable
to field biologists to whom measuring steroids in utero is often impossible. The non-human studies conducted so far have yielded
inconsistent results, perhaps due to the variety of different methods employed in measuring 2D/4D. We examined the age and
sex dependency and lateral asymmetry of 2D/4D in field voles (Microtus agrestis) and compared whether these effects differed between 2D/4D measurements taken from photographs and X-rays. Our results show
that 2D/4D measurements from photos had a higher measurement error and gave consistently higher 2D/4D than those from X-rays.
According to both measurement methods, the right paw showed higher 2D/4D values than the left paw (lateral asymmetry). Adult
voles had a lower 2D/4D than juveniles when measured from X-rays, but not when measured from photographs. We found no evidence
for a sex difference in 2D/4D using either of the measurement methods. Our findings thus suggest that X-rays, due to their
greater accuracy, should be preferred over photographs for measuring digit ratios in rodents. Our results also indicate that
in this species, 2D/4D is laterally asymmetric, but it may not be either fixed in utero or sexually dimorphic. In conclusion,
2D/4D appears to be a rather species- and method-specific measure and researchers should be careful when generalising its
applicability to study early hormonal effects in vertebrates. 相似文献
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498.
氮肥企业重大危险源安全监控系统设计 总被引:1,自引:1,他引:0
安全监控系统是重大危险源企业预防和控制生产事故的重要技术措施.以氮肥厂为案例,分析了其运营过程中存在的主要危险因素和建立重大危险源安全监控系统的技术需求,在此基础上设计了重大危险源安全监控系统,建立了基于空间信息技术的重大危险源多模式安全监控平台.该平台可以通过网络联入城市或国家重大危险源安全监控系统,有利于政府和行业部门对重大危险源的监管.借助于这样的数字化动态管理系统,可以及时获得相关参数与信息,实现早期预警,降低重大危险源企业的事故风险. 相似文献
499.
《Process Safety and Environmental Protection》2014,92(6):669-679
Several major accidents caused by metal dusts were recorded in the past few years. For instance, in 2011, three accidents caused by iron dust killed five workers at the Hoeganaes Corp. facility in Gallatin, Tennessee (USA). In order to prevent such accidents, a dynamic approach to risk management was defined in this study. The method is able to take into account new risk notions and early warnings and to systematically update the related risk. It may be applied not only in the design phase of a system, but also throughout the system lifetime as a support to a more precise and robust decision making process. The synergy of two specific techniques for hazard identification and risk assessment was obtained: the Dynamic Procedure for Atypical Scenarios Identification (DyPASI) and the Dynamic Risk Assessment (DRA) methods. To demonstrate its effectiveness, this approach was applied to the analysis of Gallatin metal dust accidents. The application allowed collecting a number of risk notions related to the plant, equipment and materials used. The analysis of risk notions by means of this dynamic approach could have led to enhanced hazard identification and dynamic real-time risk assessment. However, the approach described is effective only if associated to a proper safety culture, in order to produce an appropriate and robust decision making response to emerging risk issues. 相似文献
500.
《Environmental Hazards》2013,12(3):210-223
Traditional knowledge of disasters has been found to save lives. On remote islands where telecommunications to the mainland are unreliable, unless there are always working batteries in the radio, signs from the environment may be the only warning of an oncoming cyclone. But this knowledge is in danger of being lost, as it is an oral history not well documented, and younger people increasingly rely on technology. This article presents the results of fieldwork on remote islands in Fiji and Tonga in the South Pacific, documenting natural warning signs on islands in two different countries. The results show that there are numerous known signs, with remarkable similarities and consistencies between the two islands. This provides evidence that not only is traditional knowledge of warning signs for cyclones alive and well, the consistency in the signs suggests support for this knowledge as being just as important as western scientific knowledge. The integration of traditional knowledge and western scientific knowledge into a comprehensive warning system may help to overcome some of the limitations of the existing system and the reasons why warnings are sometimes ignored. 相似文献