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Diagnosis of Seasonal Variations of Tropical Cyclogenesis over the South China Sea Using a Genesis Potential Index 被引量:5
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作者 WANG Lei PAN Xiumei 《Journal of Ocean University of China》 SCIE CAS 2012年第3期267-278,共12页
This study examines the seasonal variations of tropical cyclogenesis over the South China Sea (SCS) using a genesis potential (GP) index developed by Emanuel and Nolan. How different environmental factors (including l... This study examines the seasonal variations of tropical cyclogenesis over the South China Sea (SCS) using a genesis potential (GP) index developed by Emanuel and Nolan. How different environmental factors (including low-level vorticity, mid-level relative humidity, vertical wind shear, and potential intensity) contribute to these variations is investigated. Composite anomalies of the GP index are produced for the summer and winter monsoons separately. These composites replicate the observed seasonal variations of the observed frequency and location of tropical cyclogenesis over the SCS. The degree of contribution by each factor in different regions is determined quantitatively by producing composites of modified indices in which only one of the contributing factors varies, with the others set to climatology. Over the northern SCS, potential intensity makes the largest contributions to the seasonal variations in tropical cyclogenesis. Over the southern SCS, the low-level relative vorticity plays the primary role in the seasonal modulation of tropical cyclone (TC) genesis frequency, and the vertical wind shear plays the secondary role. Thermodynamic factors play more important roles for the seasonal variations in tropical cyclogenesis over the northern SCS, while dynamic factors are more important in the seasonal modulation of TC genesis frequency over the southern SCS. 展开更多
关键词 tropical cyclone seasonal variation South China Sea monsoon GP index
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A NEW TECHNIQUE FOR COMPAIRING FUZZY NUMBERS USING AN INDEX OF OPTIMISM
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作者 ARSHAD MAHMOOD(阿谢德) +3 位作者 SHI Xi-zhi(史习智) XU Ji-jun(徐济鋆) 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第2期147-151,共5页
Fuzzy numbers are convenient for representing imprecise numerical quantities in a vague environment, and their comparison or ranking is very important for application purposes. Despite many methods suggested in the li... Fuzzy numbers are convenient for representing imprecise numerical quantities in a vague environment, and their comparison or ranking is very important for application purposes. Despite many methods suggested in the literature, there is no single measure that is universally applicable to a wide variety of situations. This paper suggested a new method for comparing fuzzy numbers based on the combination of maximizing possibility and minimizing possibility using an index of optimism in [0,1] reflecting the decision makers’ risk taking attitude. The method is simple, but has many comparative advantages. 展开更多
关键词 RANKING FUZZY numberS index of OPTIMISM
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Seasonal Changes of Physiological and Biochemical Indexes of Tibetan Sheep
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作者 Zhou Mingliang Chen Minghua +3 位作者 Wu Weisheng Xie Rongqing Jiang Shihai Yang Pinggui 《Animal Husbandry and Feed Science》 CAS 2016年第4期189-191,198,共4页
To investigate the seasonal changes in physiological and biochemical indexes of Tibetan sheep in Hongyuan area,we measured the physiological and biochemical indexes of Tibetan sheep at four different seasons. The resu... To investigate the seasonal changes in physiological and biochemical indexes of Tibetan sheep in Hongyuan area,we measured the physiological and biochemical indexes of Tibetan sheep at four different seasons. The results showed that the body temperature,respiration and heart rate of Tibetan sheep at four seasons were 39. 18- 39. 60 ℃,27. 20- 49. 04 times / min,91. 87- 106. 25 times / min,respectively. The indexes of WBC,MCV,MCH and MCHC in autumn and winter were significantly higher than those in spring and summer( P 〈 0. 01),while the indexes of RBC,HCT and RDW-CV in spring and summer were significantly higher than those in autumn and winter( P 〈 0. 01). The PLT did not vary greatly in spring,summer or autumn,but were all extremely higher than that in winter( P〈 0. 01). The HGB maintained stable in the four seasons. The indexes of TP,ALB and GLO in summer and autumn were extremely higher than those in winter and spring( P 〈 0. 01),while the indexes of ALP and PCHE in summer and autumn were extremely lower than those in winter and spring( P 〈 0. 01). The indexes of AST,ALT,LDH,GLU,CHOL and CA maintained stable in all seasons. 展开更多
关键词 Tibetan sheep Physiological and biochemical indexes season ADAPTABILITY
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Influential Observations in Stochastic Model of Divisia Index Numbers with AR(1) Errors
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作者 Syed Muhammed Aqil Burney Arfa Maqsood 《Applied Mathematics》 2014年第6期975-982,共8页
We use the general form of hat matrix and DFBETA measures to detect the influential observations in order to estimate the Divisia price index number when the error structure is first order serial correlation. An examp... We use the general form of hat matrix and DFBETA measures to detect the influential observations in order to estimate the Divisia price index number when the error structure is first order serial correlation. An example is presented with reference to price data of Pakistan. Hat values show the noteworthy findings that the corresponding weights of consumer items have large influence on the parameter estimates and are not affected by the parameter of autoregressive process AR(1). Whereas DFBETAs for Divisia index numbers depend on both the weights and autoregressive parameter. 展开更多
关键词 HAT Matrix DFBETA Divisia index number Influential OBSERVATION AUTOREGRESSIVE Process
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Effect of Season and Lactation Number on Milk Production of Holstein Friesian Cows in Kabul Bini-Hesar Dairy Farm
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作者 Emal Habibi M. Ibrahim Qasimi +2 位作者 Noorullah Ahmadzai Nasrin Stanikzai M. Zaher Sakha 《Open Journal of Animal Sciences》 2021年第3期369-375,共7页
<span style="font-family:Verdana;">The present study was designed to investigate the effects of season and lactation number on milk yields in Holstein dairy cows at Kabul Bini Hesar Dairy Farm. For thi... <span style="font-family:Verdana;">The present study was designed to investigate the effects of season and lactation number on milk yields in Holstein dairy cows at Kabul Bini Hesar Dairy Farm. For this purpose, data were collected from the dairy farm herd book records during 1392-1393 (2013-2014). Considering the milk yield stages of the cows, the total milk production was highest during the spring season 18</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;">454.95 </span><span style="font-family:;" "=""><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> 33</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">L followed by summer 17</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;">060.85 </span><span style="font-family:;" "=""><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> 34.5</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">L while the lowest milk production obtained in winter 16</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;">398.45 </span><span style="font-family:;" "=""><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> 31.5</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">L. Moreover, the average daily milk production of the cows w</span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> significantly different (p</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;"><</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">0.05) between the 1st, 2nd and 3</span><span style="font-family:Verdana;">rd</span><span style="font-family:Verdana;"> lactations and the amounts were 12.04 </span><span style="font-family:;" "=""><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> 0.7, 13.24 </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> 0.8 and 14.10 </span><span style="font-family:Verdana;">±</span><span><span style="font-family:Verdana;"> 0.6 L/day respectively. Milk yields of individual cows were gradually increased from 1st to 3rd lactation. The highest milk yield was rec</span><span style="font-family:Verdana;">orded in 3rd lactation and </span></span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">lowest was in 1st. From this study it was found that season and lactation number had a significant effect on the milk quantity.</span> 展开更多
关键词 season Lactation number MILK COWS Dairy Farm
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Extracting the Influential Commodities in Stochastic Model of Simple Laspeyre Price Index Numbers with AR(2) Errors
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作者 Arfa Maqsood Syed Mohammad Aqil Burney 《Open Journal of Statistics》 2014年第3期220-229,共10页
This paper, on the first hand, deals with the problem of estimation of Laspeyre price index number when the errors are assumed to be generated from AR(2) process. The general expression of hat matrix and DFBETA measur... This paper, on the first hand, deals with the problem of estimation of Laspeyre price index number when the errors are assumed to be generated from AR(2) process. The general expression of hat matrix and DFBETA measure to find the influential consumer commodities in stochastic Laspeyre price model with AR(2) errors are developed on the other. The hat values show the noteworthy findings that the corresponding weights of consumer items have large influence on the parameter estimates for simple Laspeyre price index number and are not affected by the parameter of autoregressive process of order two. While, DFBETA measures are the functions of both weights and autocorrelation parameters. Lastly, an example is presented with reference to price data of Pakistan, and shows its practical importance in financial time series. 展开更多
关键词 HAT Matrix DFBETA Laspeyre PRICE index number Influential Observation AUTOREGRESSIVE Process
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Author Index Volume 17 Numbers 1~6
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《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第6期619-621,共3页
关键词 CHEN WANG Author index Volume 17 numbers 1
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An Adaptive Parameter-Free Optimal Number of Market Segments Estimation Algorithm Based on a New Internal Validity Index
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作者 Jianfang Qi Yue Li +3 位作者 Haibin Jin Jianying Feng Dong Tian Weisong Mu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期197-232,共36页
An appropriate optimal number of market segments(ONS)estimation is essential for an enterprise to achieve successful market segmentation,but at present,there is a serious lack of attention to this issue in market segm... An appropriate optimal number of market segments(ONS)estimation is essential for an enterprise to achieve successful market segmentation,but at present,there is a serious lack of attention to this issue in market segmentation.In our study,an independent adaptive ONS estimation method BWCON-NSDK-means++is proposed by integrating a newinternal validity index(IVI)Between-Within-Connectivity(BWCON)and a newstable clustering algorithmNatural-SDK-means++(NSDK-means++)in a novel way.First,to complete the evaluation dimensions of the existing IVIs,we designed a connectivity formula based on the neighbor relationship and proposed the BWCON by integrating the connectivity with other two commonly considered measures of compactness and separation.Then,considering the stability,number of parameters and clustering performance,we proposed the NSDK-means++to participate in the integrationwhere the natural neighbor was used to optimize the initial cluster centers(ICCs)determination strategy in the SDK-means++.At last,to ensure the objectivity of the estimatedONS,we designed a BWCON-based ONS estimation framework that does not require the user to set any parameters in advance and integrated the NSDK-means++into this framework forming a practical ONS estimation tool BWCON-NSDK-means++.The final experimental results showthat the proposed BWCONand NSDK-means++are significantlymore suitable than their respective existing models to participate in the integration for determining theONS,and the proposed BWCON-NSDK-means++is demonstrably superior to the BWCON-KMA,BWCONMBK,BWCON-KM++,BWCON-RKM++,BWCON-SDKM++,BWCON-Single linkage,BWCON-Complete linkage,BWCON-Average linkage and BWCON-Ward linkage in terms of the ONS estimation.Moreover,as an independentmarket segmentation tool,the BWCON-NSDK-means++also outperforms the existing models with respect to the inter-market differentiation and sub-market size. 展开更多
关键词 Optimal number of market segments internal validity index cluster connectivity SDK-means++ market segmentation
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PLASMA SCIENCE AND TECHNOLOGY AUTHOR INDEX TO VOLUME 10 NUMBERS 1~4 (2008)
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第4期525-527,共3页
关键词 NG HE PLASMA SCIENCE AND TECHNOLOGY AUTHOR index TO VOLUME 10 numberS 1 JUN
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Author Index Page number refers to the first page of paper
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《交通运输系统工程与信息》 EI CSCD 2011年第6期216-221,共6页
关键词 JUN PAGE PING LI Author index Page number refers to the first page of paper
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THE ASYMPTOTIC SOLUTION OF THE UNSTEADY PLANAR PARALLEL GAS FLOW FOR THE CASE TEAT THE ADIABATIC INDEX NUMBER γ IS BIG
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作者 Yuan Yi-wu 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第7期649-655,共7页
In ref I,under the condition that the components of velocity are only the functions of time and polar angleθ,Drornikov solved eqss.(1.1)(1.3)of the ideal gas unsteady planar parallel potential flow.It was pointed out... In ref I,under the condition that the components of velocity are only the functions of time and polar angleθ,Drornikov solved eqss.(1.1)(1.3)of the ideal gas unsteady planar parallel potential flow.It was pointed out in ref.[1]that in general cases,the evident solutions could not he obtained.Only for two especial cases,the evident solutions were obtained.In this paper,the author studies the same prohlein as that in ref.[1].In the first section we obtain the evident solution of equations(1.1)-(1.3)under the condition that the sonic velocity is restricted by some complemental conditions.In the second section,we obtain the first-order approximate solutions of the fundamental equation for the case thatγ>>1. 展开更多
关键词 adiabalie index number gas.unsteady planar parallel flow
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Subject Index Page number refers to the first page of paper
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《交通运输系统工程与信息》 EI CSCD 2011年第6期206-215,共10页
关键词 PAGE Subject index Page number refers to the first page of paper MODE
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PLASMA SCIENCE AND TECHNOLOGY AUTHOR INDEX TO VOLUME 10 NUMBERS 1~5 (2008)
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第5期I0001-I0004,共4页
关键词 JUN NG PLASMA SCIENCE AND TECHNOLOGY AUTHOR index TO VOLUME 10 numberS 1
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PLASMA SCIENCE AND TECHNOLOGY AUTHOR INDEX TO VOLUME 10 NUMBERS 1~3 (2008)
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期403-405,共3页
关键词 NG PLASMA SCIENCE AND TECHNOLOGY AUTHOR index TO VOLUME 10 numberS 1 JUN
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Author Index Page number refers tothe first page of paper
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《交通运输系统工程与信息》 EI CSCD 2009年第6期181-186,共6页
关键词 交通运输系统工程 PAGE PING Author index Page number refers tothe first page of paper
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Subject Index Page number refers tothe first page of paper
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《交通运输系统工程与信息》 EI CSCD 2009年第6期173-180,共8页
关键词 PAGE SIMULATION Subject index Page number refers tothe first page of paper 交通运输系统工程
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Journal of Transportation Systems Engineering and Information Technology Author Index Page number refers tothe first page of paper
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《交通运输系统工程与信息》 EI CSCD 2006年第6期182-186,共5页
关键词 PING PAGE Journal of Transportation Systems Engineering and Information Technology Author index Page number refers tothe first page of paper
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Journal of Transportation Systems Engineering and Information Technology Subject Index Page number refers tothe first page of paper
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《交通运输系统工程与信息》 EI CSCD 2006年第6期174-181,共8页
关键词 PAGE Journal of Transportation Systems Engineering and Information Technology Subject index Page number refers tothe first page of paper MODE
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Relationship between Regional Rainstorm Index and Flood Disaster Ratio of Crop 被引量:8
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作者 姜会飞 廖树华 +1 位作者 潘学标 候双双 《Agricultural Science & Technology》 CAS 2011年第3期429-434,共6页
According to the daily precipitation data in Beijing area from 1985 to 2008,rainstorm weather index (10.4-38.8 mm) and climate index (daily precipitation ≥27.5 mm) in Beijing area were obtained by using the deter... According to the daily precipitation data in Beijing area from 1985 to 2008,rainstorm weather index (10.4-38.8 mm) and climate index (daily precipitation ≥27.5 mm) in Beijing area were obtained by using the determination method of extreme climate event index recommended by IPCC. Based on rainstorm weather index,rainstorm climate index and national rainstorm standard,the number of rainstorm days and rainfall amount in past years were calculated,and the correlation of annual number of rainy days,rainstorm days,precipitation and rainstorm amount with the flood disaster ratio of crop was analyzed,and the results showed that annual number of rainy days and rainstorm days couldn't reflect flood disaster ratio of crop truly,while annual precipitation and rainstorm amount had obvious linear positive correlation with the flood disaster ratio of crop. In addition,the correlation degree between rainstorm amount calculated by regional climate index and flood disaster ratio of crop was the highest,so it was suggested that rainstorm amount calculated by regional rainstorm climate index could be used to predict and evaluate flood disaster. 展开更多
关键词 RAINSTORM Rainstorm index number of rainstorm days Rainstorm amount Flood disaster
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Seasonal Dynamics of Terrestrial Net Primary Production in Response to Climate Changes in China 被引量:32
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作者 朴世龙 方精云 陈安平 《Acta Botanica Sinica》 CSCD 2003年第3期269-275,共7页
Study on seasonal responses of terrestrial net primary production (NPP) to climate changes is to help understand feedback between climate systems and terrestrial ecosystems and mechanisms of increased NPP in the north... Study on seasonal responses of terrestrial net primary production (NPP) to climate changes is to help understand feedback between climate systems and terrestrial ecosystems and mechanisms of increased NPP in the northern middle and high latitudes. In this study, time series dataset of normalized difference vegetation index (NDVI) and corresponding ground-based information on vegetation, climate, soil, and solar radiation, together with an ecological process model, were used to explore the seasonal trends of terrestrial NPP and their geographical differences in China from 1982 to 1999. As the results,. seasonal total NPP in China showed a significant increase for all four seasons (spring, summer, autumn and winter) during the past 18 years. The spring NPP indicated the largest increase rate, while the summer NPP was with the largest increase in magnitude. The response of NPP to climate changes varied with different vegetation types. The increased NPP was primarily led by an advanced growing season for broadleaf evergreen forest, needle-leaf evergreen forest, and needle-leaf deciduous forest, whilst that was mainly due to enhanced vegetation activity (amplitude of growth cycle) during growing season for broadleaf deciduous forest, broadleaf and needle-leaf mixed forest, broadleaf trees with groundcover, perennial grasslands, broadleaf shrubs with grasslands, tundra, desert, and cultivation. The regions with the largest increase in spring NPP appeared mainly in eastern China, while the areas with the largest increase in summer NPP occurred in most parts of Northwestern China, Qinghai-Xizang Plateau, Mts. Xiaoxinganling-Changbaishan, Sanjiang Plain, Songliao Plain, Sichuan Basin, Leizhou Peninsula, part of the middle and lower Yangtze River, and southeastern mountainous areas of China. In autumn, the largest NPP increase appeared in Yunnan Plateau-Eastern Xizang and the areas around Hulun Lake. Such different ways of the NPP responses depended on regional climate attributes and their changes. 展开更多
关键词 Carnegie-Ames-Stanford-Approach (CASA) model net primary production (NPP) seasonal change normalized difference vegetation index (NDVI) climate change
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