摘要
运用模糊集理论将风险评价模型的参数定义为三角模糊数,构建了水环境健康风险评价模糊模型。应用该模型不仅能够得到健康风险的各种可能值,也可以得到每一可能值对应的隶属度(或相对可信度)。而由α-截集技术,还可以进一步得到相应于不同可信度水平α的健康风险值区间。将该模糊模型应用于华北地区某城市地下水源的环境健康风险评价研究,结果表明:地下水中三氯乙烯、四氯乙烯的致癌风险均超过美国国家环保局推荐的可接受风险(1.0×10-4),可能的变化范围分别为2.06×10-4～22.03×10-4和3.67×10-4～33.29×10-4,相应的最可能风险值分别是7.22×10-4和11.54×10-4;四氯化碳虽也存在超标的可能,但情况并不严重,在不计其它污染物带来的致癌风险的情况下,受污染水源水环境健康危害总风险的可能变化区间为5.86×10-4～56.67×10-4,最可能风险值为19.21×10-4。实例研究表明,以模糊集理论评价水环境健康风险水平是可行的。
The fuzzy set theory is applied to define the parameters of assessment model as triangular fuzzy parameters to establish a fuzzy risk assessment model for environmental health. This method can solve the problems happened to conventional risk assessment methods including the errors due to the uncertainty of assessment system and scarcity of available data. By using this model not only the value of probable risk indexes of specific substance influencing people＇ s health but also their corresponding membership degrees （or relative confidence levels） can be obtained. The α-cut technique helps to further convert the fuzzy risk into an interval value corresponding to the confidence level of α. The model is applied to assess the recommended by U. S. EPA. The most likely risk values of TCE and PCE are 7.22 × 10^-4 and 11.54 ×10^-4 respectively. The most probable value of cancerous risk index for polluted groundwater supply source is 19.21× 10^-4.
出处
《水利学报》
EI
CSCD
北大核心
2007年第8期895-900,共6页
Journal of Hydraulic Engineering
基金
安徽省自然科学基金资助项目(050450303)
关键词
不确定信息
水源
环境健康风险评价
三角模糊数
α-截集
uncertain information
urban water source
risk assessment of environmental health
triangular fuzzy parameter
α-cut technique
