This study studied the characteristics and source apportionment of heavy metal pollution in the agricultural soil surrounding a gangue coal heap in Chongqing,China by using absolute principal component scores-multiple...This study studied the characteristics and source apportionment of heavy metal pollution in the agricultural soil surrounding a gangue coal heap in Chongqing,China by using absolute principal component scores-multiple linear regression(APCSMLR)model and positive matrix factorization(PMF)model.The applicability of the models was compared in the assessment of source apportionment.The results showed that the average contents of Cd,Hg,As,Pb,Cr,Cu,Ni,and Zn in the surface soil were 0.46,0.14,9.66,31.2,127,95.6,76.0,and 158 mg/kg,respectively.Combined with the spatial distribution and correlation analyses,the results of source apportionment were consistent for both the APCSMLR and PMF models.Cd,Hg,As,and Pb were mainly affected by the gangue heap accumulation,with respective contributions of 74.6%,79.4%,69.1%,and 67.2%based on the APCS-MLR model and respective contributions of 69.7%,60.7%,57.4%,and 41.9%based on the PMF model.Ni and Zn were mainly affected by industrial and agricultural activities,while Cr and Cu were mainly affected by natural factors.The results of the source apportionment were approximately consistent between the APCS-MLR and PMF models.The combined application of the two receptor models can make the results of source apportionment more comprehensive,accurate,and reliable.展开更多
目前有关堆的取证研究主要是针对Windows系统的堆和NT堆,然而怎样从转储文件中提取出Linux系统Glibc堆信息并没有得到充分的研究。为了重现Linux系统中Glibc堆的内部信息,采用内存对象vtype描述信息中字段偏移定位结合在内存中Glibc堆...目前有关堆的取证研究主要是针对Windows系统的堆和NT堆,然而怎样从转储文件中提取出Linux系统Glibc堆信息并没有得到充分的研究。为了重现Linux系统中Glibc堆的内部信息,采用内存对象vtype描述信息中字段偏移定位结合在内存中Glibc堆实现的方法提取Glibc堆内部信息。并基于此方法研发了基于Rekall框架的3个堆信息提取插件。还研究了house of spirit类型的堆攻击,建立了攻击模型并提取其攻击特征。基于提取的攻击特征设计出针对house of spirit攻击的检测算法。在堆信息提取插件的基础上研发了攻击检测插件。实验结果表明本方法可以有效地提取Linux系统进程中堆在内存中的信息,并且基于这些信息结合攻击检测算法成功检测内存中的house of spirit类型攻击。展开更多
基金supported by Project of Chongqing Ecology and Environment Bureau(2021111)Project of Chongqing Science and Technology Bureau(cstc2022jxjl0005)。
文摘This study studied the characteristics and source apportionment of heavy metal pollution in the agricultural soil surrounding a gangue coal heap in Chongqing,China by using absolute principal component scores-multiple linear regression(APCSMLR)model and positive matrix factorization(PMF)model.The applicability of the models was compared in the assessment of source apportionment.The results showed that the average contents of Cd,Hg,As,Pb,Cr,Cu,Ni,and Zn in the surface soil were 0.46,0.14,9.66,31.2,127,95.6,76.0,and 158 mg/kg,respectively.Combined with the spatial distribution and correlation analyses,the results of source apportionment were consistent for both the APCSMLR and PMF models.Cd,Hg,As,and Pb were mainly affected by the gangue heap accumulation,with respective contributions of 74.6%,79.4%,69.1%,and 67.2%based on the APCS-MLR model and respective contributions of 69.7%,60.7%,57.4%,and 41.9%based on the PMF model.Ni and Zn were mainly affected by industrial and agricultural activities,while Cr and Cu were mainly affected by natural factors.The results of the source apportionment were approximately consistent between the APCS-MLR and PMF models.The combined application of the two receptor models can make the results of source apportionment more comprehensive,accurate,and reliable.
文摘目前有关堆的取证研究主要是针对Windows系统的堆和NT堆,然而怎样从转储文件中提取出Linux系统Glibc堆信息并没有得到充分的研究。为了重现Linux系统中Glibc堆的内部信息,采用内存对象vtype描述信息中字段偏移定位结合在内存中Glibc堆实现的方法提取Glibc堆内部信息。并基于此方法研发了基于Rekall框架的3个堆信息提取插件。还研究了house of spirit类型的堆攻击,建立了攻击模型并提取其攻击特征。基于提取的攻击特征设计出针对house of spirit攻击的检测算法。在堆信息提取插件的基础上研发了攻击检测插件。实验结果表明本方法可以有效地提取Linux系统进程中堆在内存中的信息,并且基于这些信息结合攻击检测算法成功检测内存中的house of spirit类型攻击。
