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
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
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
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
<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
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
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
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
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
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
基金funded by the tropical marine meteorology fund from the Institute of Tropical and Marine Meteorology CMAthe National Basic Research Program of China(2011CB403500)+2 种基金SOED1108LED1002the Fundamental Research Funds for the Central Universities (No.11lgpy13)
文摘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.
文摘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.
基金Supported by Achievement Transformation Project of Science & Technology Department of Sichuan Province "Hybridization Improvement and Demonstration Promotion of Tibetan Sheep with White Suffolk Sheep"
文摘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.
文摘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.
文摘<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>
文摘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.
基金supported by the earmarked fund for CARS-29 and the open funds of the Key Laboratory of Viticulture and Enology,Ministry of Agriculture,China.
文摘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.
文摘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.
基金Supported by Cultivation Fund for Scientific and Technical innovation Project of Higher Education of Ministry of Education of China(708013)National Key Technology R &D Program in the 11th Five Year Plan of China (2008BAK50B02, 2007BAC29B05)~~
文摘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.
文摘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.