摘要
为了研究长沙市大气颗粒物的统计分布特性,选定4种理论分布函数(伽马分布、对数正态分布、韦伯分布和皮尔逊分布)拟合长沙市大气颗粒物PM10质量浓度样本,采用矩估计和极大似然估计法求解分布函数的参数;使用双参数指数分布函数描述高质量浓度PM10的尾部分布特性。研究结果表明:长沙市大气颗粒物PM10的整体分布特性为伽马分布,高质量浓度PM10的尾部分布为双参数指数分布。根据双参数指数分布PM10质量浓度超过国家空气质量日平均质量浓度标准的频率为8.5%;PM10达到国家标准所需要的污染源散发强度的降低量为35.8%。
In order to analyze the PM10 mass concentration distribution,four theoretical parent frequency distribution functions,i.e.lognormal,Weibull,Gamma and Pearson V were used to fit the complete set of PM10 mass concentration in Changsha.The method of moment and the method of maximum likelihood were used to estimate the parameters.Two parameters exponential distribution was used to fit the high concentration of PM10.The results show that Gamma distribution is the best one to represent the performance of PM10 concentration while two parameters exponential distribution fits the high concentration of PM10 well.According to the two parameters exponential distribution the frequency of exceeding the air quality standard(AQS) is 8.5%,and the estimated emission source reduction of PM10 should be 35.8% to meet the assigned standard.
出处
《中南大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2012年第4期1567-1573,共7页
Journal of Central South University:Science and Technology
基金
高等学校全国优秀博士学位论文作者专项资金资助项目(FANEDD200545)
国家自然科学基金资助项目(NSFC51178466)
国家科技支撑计划项目(2008BAJ12B03)
关键词
母体分布
双参数指数分布
污染源降低量
超标频率
parent distribution
two-parameter exponential distribution
emission source reduction
frequency of exceeding the AQS