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Indices of El Nio and El Nio Modoki:An Improved El Nio Modoki Index 被引量:4
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作者 李根 任保华 +1 位作者 杨成昀 郑建秋 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第5期1210-1220,共11页
In recent years, El Nino Modoki (a type of pseudo-El Nino) has been distinguished as a unique large-scale ocean warming phenomenon happening in the central tropical Pacific that is quite different from the tradition... In recent years, El Nino Modoki (a type of pseudo-El Nino) has been distinguished as a unique large-scale ocean warming phenomenon happening in the central tropical Pacific that is quite different from the traditional El Nino. In this study, EOF analysis was used to successfully separate El Nino and El Nino Modoki. The abilities of the NINO3 index, NINO3.4 index, NINO1+2 index and NINO4 index in characterizing El Nino were explored in detail. The resulting suggestion was that, comparatively, NINO3 is the optimal index for monitoring El Nino among the four NINO indices, as the other NINO indices were found to be less good at distinguishing between El Nino and El Nino Modoki signals, or were easily disturbed by El Nino Modoki signals. Further, an improved El Nino Modoki index (IEMI) was introduced in the current paper to better represent the El Nino Modoki that is captured by the second leading EOF mode of monthly tropical Pacific sea surface temperature anomalies (SSTAs). The IEMI is an improvement of the El Nino Modoki index (EMI) through adjustments made to the inappropriate weight coefficients of the three boxes of EMI. The IEMI therefore overcomes the EMI’s inability to monitor the two historical El Nino Modoki events, as well as avoids the possible risk (present in the EMI) of excluding the interference of the El Nino signal. The realistic and potential advantages of the IEMI are clear. 展开更多
关键词 El Nino El Nino Modoki NINO3 index improved El Nino Modoki index (IEMI)
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An Improved Indexing and Matching Method for Mathematical Expressions Based on Inter-Relevant Successive Tree
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作者 Huicong Liu Xuedong Tian +2 位作者 Bingjie Tian Fang Yang Xinfu Li 《Journal of Computer and Communications》 2016年第15期63-78,共17页
In recent years, a growing number of math contents are available on the Web. When conventional search engines deal with mathematical expressions, the two-dimen- sion-al structure of mathematical expressions is lost, w... In recent years, a growing number of math contents are available on the Web. When conventional search engines deal with mathematical expressions, the two-dimen- sion-al structure of mathematical expressions is lost, which results in a low performance of math retrieval. While the retrieval technology specifically designed for mathematical expressions is not mature currently. Aiming at these problems, an improved mathematical expression indexing and matching method was proposed through employing full text index method to deal with the two-dimensional structure of mathematical expressions. Firstly, through the fully consideration of LaTeX formulae’ characteristics, a feature representation method of mathematical expressions and a clustering method of feature keywords were put forward. Then, an improved inter-relevant successive trees index model was applied to the construction of the mathematical expression index, in which the cluster algorithm of mathematical expression features was employed to solve the problem of the quantity growth of the trees in processing large amount of formulae. Finally, the matching algorithms of mathematical expressions were given which provide four query modes called exact matching, compatible matching, sub-expression matching and fuzzy matching. In browser/server mode, 110027 formulae were used as experimental samples. The index file size was 29.02 Mb. The average time of retrieval was 1.092 seconds. The experimental result shows the effectiveness of the method. 展开更多
关键词 Mathematical Expression Retrieval Improved Math index Inter-Relevant Successive Tree Clustering MATCHING
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New PAMA Technology Helps Tackle the New Challenges of China Automotive Sector
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作者 Alex Tsay 《润滑油》 CAS 2010年第1期31-38,共8页
Polyalkylmethacrylate (PAMA) based viscosity index improver (VII) and pour point depressant (PPD), with the versatile chemistry and unique performance characteristics, are widely used in advanced formulations, enablin... Polyalkylmethacrylate (PAMA) based viscosity index improver (VII) and pour point depressant (PPD), with the versatile chemistry and unique performance characteristics, are widely used in advanced formulations, enabling fluids to meet rheological requirement of modern specifications. This paper will be dedicated to the application of PAMA in helping China automotive lubricant formulators tackle the challenges of improving fuel economics from using lower viscosity fluids, of better protection strengthten in transmission performance and meeting new global specifications for low temperature performance. 展开更多
关键词 polyalkylmethacrylate viscosity index improver pour point depressant automatic transmission fluid gear oil ROBO test
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Water Quality Analysis of Fuping Section of the Shichuan River Based on Different Evaluation Methods
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作者 Xiaoyan WANG Jinhua ZHANG +2 位作者 Jing WANG Yating PANG Pei ZHANG 《Meteorological and Environmental Research》 CAS 2022年第6期63-67,共5页
In order to study the water quality of the Shichuan River basin in Fuping,Shaanxi Province,based on improved Nemerow index method,comprehensive pollution index method and principal component analysis method,eight wate... In order to study the water quality of the Shichuan River basin in Fuping,Shaanxi Province,based on improved Nemerow index method,comprehensive pollution index method and principal component analysis method,eight water quality indexes such as pH,dissolved oxygen(DO),total dissolved solids(TDS),COD,total hardness,total phosphorus,total nitrogen and Zn in three monitoring sections of Fuping section of the Shichuan River in Shaanxi Province were detected and analyzed.The results show that the water quality of the surface water in the Shichuan River basin is gradeⅢorⅣwater,that is,the water is slightly polluted and moderately polluted.It is necessary to monitor the water quality after regulation and clarify the main factors causing the water pollution. 展开更多
关键词 Water quality evaluation Improved Nemero index method Comprehensive pollution index method Principal component analysis Shichuan River
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Water quality characteristics and assessment of Yongding New River by improved comprehensive water quality identification index based on game theory 被引量:9
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作者 Yu Liu Yucheng Hu +2 位作者 Yumei Hu Yuqi Gao Zhenying Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第6期40-52,共13页
The Yongding New River is essential for the water supplies of Tianjin.To date,there is no comprehensive report that assesses the year-round water quality of the Yongding New River Main stream.Moreover,little attention... The Yongding New River is essential for the water supplies of Tianjin.To date,there is no comprehensive report that assesses the year-round water quality of the Yongding New River Main stream.Moreover,little attention has been given to determining a combined weight for improving the traditional comprehensive water quality identification index(ICWQII)by the game theory.Seven water quality parameters were investigated monthly along the main stream of the Yongding New River from May 2018 to April 2019.Organic contaminants and nitrogen pollution were mainly caused by point sources pollution,and the total phosphorus mainly by non-point source pollution.Dramatic spatio-temporal variations of water quality parameters were jointly caused by different pollutant sources and hydrometeorological factors.In terms of this study,an improved comprehensive water quality identification index(ICWQII)based on entropy weight or variation coefficient and traditional CWQII underestimated the water qualities,and an ICWQII based on the superstandard multiple method overvalued the assessments.By contrast,water qualities assessments done with an ICWQII based on the game theory matched perfectly with the practical situation.The ICWQII based on game theory proposed in this study takes into account not only the degree of disorder and variation of water quality data,but also the influence of standard-exceeded pollution indicators,whose results are relatively reasonable.All findings and the ICWQII based on game theory can provide scientific support for decisions related to the water environment management of the Yongding New River and other waters. 展开更多
关键词 Water quality assessment Improved comprehensive water quality identification index Game theory Combined weight Spatio-temporal variation Yongding New River
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An improved risk of malignancy index in diagnosis of adnexal mass 被引量:2
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作者 WANG Li-ming SONG Hao +1 位作者 SONG Xiao ZHOU Xiao-bin 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第3期533-535,共3页
Background With the advent of color Doppler flow imaging (CDFI) and technological development of detection of serum tumor markers,new opportunities are presented to the improved risk of malignancy index (RMI) base... Background With the advent of color Doppler flow imaging (CDFI) and technological development of detection of serum tumor markers,new opportunities are presented to the improved risk of malignancy index (RMI) based on Jacobs'research for predicting ovarian malignancy in patients with adnexal masses.Methods One hundred and eighty women with an adnexal mass admitted for primary laparotomy were studied.Tumor specific growth factor (TSGF) adjusted ultrasound scores and the results of Doppler blood flow analysis were obtained before the operation.Based on the parameters which had been studied in Jacobs' research,TSGF levels and the findings of color Doppler flow imaging,the risk of malignancy model was redesigned using a binary Logistic regression model.The diagnostic efficacy of the improved risk of malignancy index (improved RMI) was compared with the Jacobs'model RMI by receiver operator characteristic (ROC) curve.Results The ROC curve showed a higher sensitivity (Mcnamer's test,P 〈0.05) in the discrimination between benign and malignant adnexal masses for the improved RMI than the RMI.Compared with the RMI,the improved RMI had an advantage in prediction of ovarian germ cell tumors and granular cell tumor (28.57% vs.71.43%,P 〈0.05) and the early stage tumors and borderline tumors (33.33% vs.66.67%,P〈0.05).Conclusion The predictability of the improved RMI is better than the classic Jacobs' model,especially in diagnosis of the ovarian germ cell tumors and granular cell tumor and other early stage adnexal tumors. 展开更多
关键词 improved risk of malignancy index adnexal mass MALIGNANT DIAGNOSIS
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