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171.
A central part of probabilistic public health risk assessment is the selection of probability distributions for the uncertain input variables. In this paper, we apply the first-order reliability method (FORM)(1–3) as a probabilistic tool to assess the effect of probability distributions of the input random variables on the probability that risk exceeds a threshold level (termed the probability of failure) and on the relevant probabilistic sensitivities. The analysis was applied to a case study given by Thompson et al. (4) on cancer risk caused by the ingestion of benzene contaminated soil. Normal, lognormal, and uniform distributions were used in the analysis. The results show that the selection of a probability distribution function for the uncertain variables in this case study had a moderate impact on the probability that values would fall above a given threshold risk when the threshold risk is at the 50th percentile of the original distribution given by Thompson et al. (4) The impact was much greater when the threshold risk level was at the 95th percentile. The impact on uncertainty sensitivity, however, showed a reversed trend, where the impact was more appreciable for the 50th percentile of the original distribution of risk given by Thompson et al. 4 than for the 95th percentile. Nevertheless, the choice of distribution shape did not alter the order of probabilistic sensitivity of the basic uncertain variables.  相似文献   
172.
Perception of Ecological Risk to Water Environments   总被引:12,自引:1,他引:12  
This paper examines lay and expert perceptions of the ecological risks associated with a range of human activities that could adversely affect water resource environments. It employs the psychometric paradigm pioneered in characterizing perceptions of human health risks, which involves surveys to obtain judgments from subjects about risk items in terms of several important characteristics of the risks. The paper builds on a previous study that introduced ecological risk perception. This second study employs a larger, more diverse sample, a more focused topic area, and comparisons between lay and expert judgments. The results confirm that a small set of underlying factors explain a great deal of variability in lay judgments about ecological risks. These have been termed Ecological Impact, Human Benefits, Controllability , and Knowledge. The results are useful in explaining subjects' judgments of the general riskiness of, and need for regulation of, various risk items. The results also indicate several differences and areas of agreement among the lay and expert samples that point to potential key issues in future ecological risk management efforts for water resources.  相似文献   
173.
On the basis of discussion and analysis during and following an ATSDR science panel on the bioavailability of mercury in soils, it is apparent that the default assumption of 100% relative bioavailability for mercury-contaminated soils is excessively conservative. However, current knowledge does not allow the development of default assumptions or guidelines for determining relative bioavailability of mercury in soils. Until such default assumptions or guidelines can be developed, site-specific assays of bioavailability, preferably using either animal bioassays or validated in vitro techniques, may provide the best approach for estimating soil-mercury bioavailability.  相似文献   
174.
The aim of this case study is to discuss the role of technology in addressing environmental problems. The paper tries to scratch beneath the surface of the increasingly frequent ‘quick-fix’ solutions to the present environmental problems, based on such beguiling catchwords as Cleaner Technologies, Best Available Technologies, and Best Available Technologies Not Exceeding Excessive Costs, etc., in an attempt to discover whether there is any substance in them, or whether they are just full of hot air. Recent data from case studies performed by the author in Germany and Finland as well as a postal questionnaire in Denmark are presented. The paper analyses and discusses the roles and responsibilities of designers, industrialists, and government policy-makers. It is argued that existing regulatory regimes, supranational industrial structures, and market mechanisms do not favour the development of cleaner technologies, nor do they promote a reduction in consumption patterns. Evidence from ongoing empirical research in Northwest Europe suggests that industry is far from developing and/or implementing cleaner technologies. The paper closes with a discussion of some of the policy implications involved and some examples of urgently needed further research.  相似文献   
175.
从系统的角度分析了高新技术企业财务管理的特点和不确定性,在此基础上提出了高新技术企业财务管理柔性的概念,构建了财务管理柔性、柔性净效益及其变动幅度的度量方法,运用预控图原理对财务管理柔性进行动态监控。应用实例表明,该方法易于操作,为财务管理柔性评价奠定了基础。  相似文献   
176.
在全球卫生领域以大型会议为代表的国际会议外交已成为全球卫生治理的一种重要形式和载体。文章梳理了全球卫生治理中会议外交的两方面体现,一是以国际会议为代表的会议外交与全球卫生治理,二是以国家行为体为代表的会议外交与全球卫生治理,并进一步归纳了会议外交促成的全球卫生治理进程,包括多次会议促成了全球卫生安全的国际规则《国际卫生条例》,以及历经多年会议磋商促成了全球人口覆盖范围广的《烟草控制框架公约》。中共的十九大报告中对外交工作和健康中国战略有了明确表述,由此需要卫生与外交工作者审时度势、认清角色,通过会议外交表明态度,并以全球卫生会议外交为起点,促进国内立法接续。  相似文献   
177.
以计划行为理论为基础,利用调研获取的农户数据,分析了农户当前对于低碳属性农业技术的采用现状,并采用多层Logistic回归模型估计了农业项目和农户两个层面因素对农户低碳农业技术后续采用意愿所产生的影响。结果表明:农户对于低碳农业技术采用后的效果评价较好,技术需求度和后续采用意愿均处于较高的水平上,并且不同类型农户对当前低碳农业技术的采用程度、偏好程度存在一定差异;农业生产项目和农户经营主体两个层面的因素均对农户低碳农业技术后续采用意愿产生重要影响,且对于不同类型农户后续采用意愿的作用效果存在一定差异,其中农业项目的地理特征、经济效益、资金技术要素投入强度和农户的行为意向产生的影响作用较强;农户技术采用强度受到农户个体特征和行为意向的显著影响,且作用效果在不同类型农户之间存在明显差异。  相似文献   
178.
核电站组织风险已经成为核电站安全运行重要的影响因素,在概率安全评价中考虑组织风险因素是核电安全研究的重要课题。文章在建立组织风险因素与PSA之间转换的概念框架的基础上,对组织风险因素进行分类。分类后的组织风险因素受人员行为形成因子的影响,其影响在人因可靠性分析中进行分析。计算和评估这些人员行为形成因子对于事故后操纵员的影响可以计算组织因素对核电站安全的影响。  相似文献   
179.
企业用户云服务技术选择行为   总被引:1,自引:0,他引:1  
如何选择最佳云服务方案,是企业决定采纳云服务之后所面临的一个重要决策。为了解决云服务技术选择问题,从业务流程的视角出发,以模块化系统理论为基础,提出一个流程模块化、IT可拆解性及安全风险如何影响云服务技术选择的研究模型。采用问卷调查和计量经济学的普通最小二乘法OLS进行实证分析。研究结果表明:流程模块化和IT可拆解性对云服务技术选择的抽象程度有显著的正向影响,即流程模块化程度IT可拆解性越高的企业,越倾向于选择抽象程度高的云服务,如软件即服务SaaS;而流程模块化程度和IT可拆解性越低的企业,越倾向于选择抽象程度低的云服务,如基础设施即服务IaaS。同时,安全风险会正向调节流程模块化和IT可拆解性对云服务技术选择的抽象程度的影响。  相似文献   
180.
This study explores the use of Computer-Supported Collaborative Work (CSCW) technologies, by way of a computer-based system called iCohere. This system was used to facilitate collaboration conducting Community-Based Participatory Research (CBPR). Data was gathered from 13 members of a Community Collaborative Board (CCB). Analysis revealed that iCohere served the following functions: facilitating communication, providing a depository for information and resource sharing, and allowing for remote meeting attendance. Results indicated that while iCohere was useful in performing these functions, less expensive technologies had the potential to achieve similar goals if properly implemented. Implications for future research on CSCW systems and CBPR are discussed.  相似文献   
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