Offshore project risk concerns many influence factors with complex relationship, and traditional methods cannot be used for the evaluation on risk probability. To deal with this problem, a new method was developed by ...Offshore project risk concerns many influence factors with complex relationship, and traditional methods cannot be used for the evaluation on risk probability. To deal with this problem, a new method was developed by the combination of improved technique for order preference by similarity ideal solution method, analytical hierarchy process method and the network response surface method. The risk probability was calculated by adopting network response surface analysis based on the state variable of a known event and its degree of membership.This quantification method was applied to an offshore platform project, Bonan oil and gas field project in Bohai Bay in June 2004.There were 7 sub-projects and each includes 4 risk factors.The values of 28 risk factors, ranging from 10^-6 to 10^-4, were achieved. This precision conforms to the international principle of as low as reasonably practically.The evaluation indicates that the values of comprehensive level of construction group and ability of technical personnel on the spot are relatively high among all risk factors, so these two factors should be paid more attention to in offshore platform construction.展开更多
With rapid economic and social development, soil contamination arising from heavy metals has become a serious problem in many parts of China. We collected a total of 445 samples （0-20 cm） at the nodes of a 2 kmx2 km...With rapid economic and social development, soil contamination arising from heavy metals has become a serious problem in many parts of China. We collected a total of 445 samples （0-20 cm） at the nodes of a 2 kmx2 km grid in surface soils of Rizhao city, and analyzed sources and risk pattern of 10 heavy metals （As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb and Zn）. The combination of Multivariate statistics analysis and Geostatistical methods was applied to identify the sources and hazardous risk of heavy metals in soils. The result indicated that Cr, Ni, Co, Mn, Cu, and As were mainly controlled by parent materials and came from natural sources. Cd and Hg originated from anthropogenic sources. Pb and Zn, belonging to different groups in multivariate analysis, were associated with joint effect of parent materials and human inputs. Ordinary Kriging and Indicator Kriging suggested that single element and elements association from the same principal components had similar spatial distribution. Through comprehensive assessment on all elements, we also found the high risk areas were located in the populated urban areas and western study area, which could be attributed to the higher geological background in the western part and strong human interference in the eastern part.展开更多
文摘Offshore project risk concerns many influence factors with complex relationship, and traditional methods cannot be used for the evaluation on risk probability. To deal with this problem, a new method was developed by the combination of improved technique for order preference by similarity ideal solution method, analytical hierarchy process method and the network response surface method. The risk probability was calculated by adopting network response surface analysis based on the state variable of a known event and its degree of membership.This quantification method was applied to an offshore platform project, Bonan oil and gas field project in Bohai Bay in June 2004.There were 7 sub-projects and each includes 4 risk factors.The values of 28 risk factors, ranging from 10^-6 to 10^-4, were achieved. This precision conforms to the international principle of as low as reasonably practically.The evaluation indicates that the values of comprehensive level of construction group and ability of technical personnel on the spot are relatively high among all risk factors, so these two factors should be paid more attention to in offshore platform construction.
基金China State-Sponsored Postgraduate Study Abroad Program,No.201306190053National Natural Science Foundation of China,No.41101079+1 种基金The Program B for Outstanding PhD Candidate of Nanjing University,No.2014001B008The Program for Graduate Student’s Research Innovation of Jiangsu Province,No.CXLX13-051
文摘With rapid economic and social development, soil contamination arising from heavy metals has become a serious problem in many parts of China. We collected a total of 445 samples （0-20 cm） at the nodes of a 2 kmx2 km grid in surface soils of Rizhao city, and analyzed sources and risk pattern of 10 heavy metals （As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb and Zn）. The combination of Multivariate statistics analysis and Geostatistical methods was applied to identify the sources and hazardous risk of heavy metals in soils. The result indicated that Cr, Ni, Co, Mn, Cu, and As were mainly controlled by parent materials and came from natural sources. Cd and Hg originated from anthropogenic sources. Pb and Zn, belonging to different groups in multivariate analysis, were associated with joint effect of parent materials and human inputs. Ordinary Kriging and Indicator Kriging suggested that single element and elements association from the same principal components had similar spatial distribution. Through comprehensive assessment on all elements, we also found the high risk areas were located in the populated urban areas and western study area, which could be attributed to the higher geological background in the western part and strong human interference in the eastern part.
