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空气污染的计量评估方法 被引量:1
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作者 黄宏运 吕石山 朱家明 《阴山学刊(自然科学版)》 2016年第4期99-103,共5页
针对形式日益严峻的空气污染问题,通过评估指标模糊识别化、构建评价等级矩阵、计算欧氏距离贴近度等方法构建评估空气污染程度的计量模型,运用该模型对安徽省各市2015年1月至2016年3月的空气污染程度进行评估,评估结果按优、良、中度... 针对形式日益严峻的空气污染问题,通过评估指标模糊识别化、构建评价等级矩阵、计算欧氏距离贴近度等方法构建评估空气污染程度的计量模型,运用该模型对安徽省各市2015年1月至2016年3月的空气污染程度进行评估,评估结果按优、良、中度污染、重度污染和严重污染六个等级进行了区域分布统计分析,评估结果表明安徽省空气污染状况比较严重。 展开更多
关键词 空气污染评估 评价等级矩阵 欧式距离 MATLAB EXCEL
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Noninvasive assessment of hepatic fibrosis in Egyptian patients with chronic hepatitis C virus infection 被引量:6
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作者 Shawky Abdelhamid Fouad Serag Esmat +2 位作者 Dalia Omran Laila Rashid Mohamed H Kobaisi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第23期2988-2994,共7页
AIM: To evaluate the accuracy of specific biochemical markers for the assessment of hepatic fibrosis in patients with chronic hepatitis C virus (HCV) infection. METHODS: One hundred and fifty-four patients with chroni... AIM: To evaluate the accuracy of specific biochemical markers for the assessment of hepatic fibrosis in patients with chronic hepatitis C virus (HCV) infection. METHODS: One hundred and fifty-four patients with chronic HCV infection were included in this study; 124 patients were non-cirrhotic, and 30 were cirrhotic. The following measurements were obtained in all patients: serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, total bilirubin, prothrombin time and concentration, complete blood count, hepatitis B surface antigen (HBsAg), HCVAb, HCV-RNA by quantitative polymerase chain reaction, abdominal ultrasound and ultrasonic-guided liver biopsy. The following ratios, scores and indices were calculated and compared with the results of the histopathological examination: AST/ALT ratio (AAR), age platelet index (API), AST to platelet ratio index (APRI), cirrhosis discriminating score (CDS), Pohl score, G teborg University Cirrhosis Index (GUCI). RESULTS: AAR, APRI, API and GUCI demonstrated good diagnostic accuracy of liver cirrhosis (80.5%, 79.2%, 76.6% and 80.5%, respectively); P values were: < 0.01, < 0.05, < 0.001 and < 0.001, respectively. Among the studied parameters, AAR and GUCI gave the highest diagnostic accuracy (80.5%) with cutoff values of 1.2 and 1.5, respectively. APRI, API and GUCI were significantly correlated with the stage of fibrosis (P < 0.001) and the grade of activity (P < 0.001, < 0.001 and < 0.005, respectively), while CDS only correlated significantly with the stage of fibrosis (P < 0.001) and not with the degree of activity (P > 0.05). In addition, we found significant correlations for the AAR, APRI, API, GUCI and Pohl score between the non-cirrhotic (F0, F1, F2, F3) and cirrhotic (F4) groups (P values: < 0.001, < 0.05, < 0.001, < 0.001 and < 0.005, respectively; CDS did not demonstrate significant correlation (P > 0.05). CONCLUSION: The use of AAR, APRI, API, GUCI and Pohl score measurements may decrease the need for liver biopsies in diagnosing cirrhosis, especially in Egypt, where resources are limited. 展开更多
关键词 Age platelet index Aspartate aminotrans-ferase platelet ratio index Aspartate aminotransferase-to-alanine aminotransferase ratio Cirrhosis discrimi-nating score Fibrosis evaluation G^teborg UniversityCirrhosis Index Hepatitis C virus infection Liver fibro-sis Pohl score
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Study on the Environmental Quality Guarantee Ratio on the Basis of Total Air Pollutant Emission Amount Control
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作者 徐芙蓉 施介宽 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期38-41,共4页
The hourly and daily air quality concentration in the total air pollutant emission amount control zone is not sure to be continuously up to national ambient air quality standard, even though the total annual air pollu... The hourly and daily air quality concentration in the total air pollutant emission amount control zone is not sure to be continuously up to national ambient air quality standard, even though the total annual air pollutant emission is permitted under the total air pollutant emission amount control (TAPEAC) on the basis of A-value method. So the concept of the environmental quality guarantee ratio (EQGR) for TAPEAC is advanced in this paper and its quantitative formula is figured out for both hourly and daily EQGR. It is concluded that the EQGR is related with the yearly arrangement of A-value besides the pollutant type. According to the meteorological data in a lower area along Yangtze River in 2000, the yearly A-value trend is analyzed. Based on the data, the hourly EQGR of SO 2 and NO 2 is respectively 97.4% and 90.2%, and daily EQGR respectively 90.2% and 79.5%. 展开更多
关键词 Total Air Pollutant Emission Amount Control (TAPEAC) A-value Method Guarantee Ratio Yangtze River.
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Terahertz-dependent PM2.5 monitoring and grading in the atmosphere 被引量:1
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作者 XinYang Miao HongLei Zhan +4 位作者 Kun Zhao ZhenWei Zhang Lei Xu CunLin Zhang LiZhi Xiao 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第10期60-69,共10页
Rapid industrialization and economic development have led to serious pollution in the form of fine particulate matter(PM2.5,particulate matter with a diameter of less than 2.5 μm). In China, PM2.5 has been one of the... Rapid industrialization and economic development have led to serious pollution in the form of fine particulate matter(PM2.5,particulate matter with a diameter of less than 2.5 μm). In China, PM2.5 has been one of the most debated topics in councils of government and issues of public concern. Terahertz(THz) radiation was employed to measure the PM2.5 in the atmosphere from September 2014 to April 2015 in Beijing. Comparison of the PM2.5 level from the website with THz absorbance revealed a significant phenomenon: THz radiation can be used to monitor PM2.5 in the atmosphere. During Asia-Pacific Economic Cooperation(APEC) 2014, "APEC Blue" was also recorded in a THz system. The relationship between absorbance and PM2.5 demonstrates that THz radiation is an effective selection for air pollution grading. Based on the absorbance spectra, the elemental compositions were studied by two-dimensional correlation spectroscopy(2 DCOS) in conjunction with X-ray fluorescence.Several single absorption peaks were revealed and caused by sulphate from coal combustion, vehicle exhaust emissions and secondary reactions. Furthermore, mathematical algorithms, such as the BPANN and SVM, can process the THz absorbance data and greatly improve the precision of the estimation of PM2.5 mass. Our results suggest that THz spectroscopy can not only reveal the component information for pollution source determination, but quantitatively monitor the PM2.5 content for pollution level evaluation. Therefore, the use of THz radiation is a new method for future air pollution monitoring and grading systems. 展开更多
关键词 TERAHERTZ PM2.5 MONITORING GRADING
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