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理财业务发展对商业银行收益及风险的影响研究--基于15家A股上市银行的实证分析 被引量:5
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作者 姚晓垒 《金融监管研究》 北大核心 2018年第3期54-63,共10页
近年来,我国商业银行理财业务快速发展,在产生收益的过程中也积聚了一定风险,引起监管部门和社会的高度关注。本文基于15家A股上市银行2011-2016年的面板数据,深入剖析了理财业务发展对我国商业银行收益及风险的影响。实证结果表明:发... 近年来,我国商业银行理财业务快速发展,在产生收益的过程中也积聚了一定风险,引起监管部门和社会的高度关注。本文基于15家A股上市银行2011-2016年的面板数据,深入剖析了理财业务发展对我国商业银行收益及风险的影响。实证结果表明:发展理财业务对提高商业银行整体资产收益率有积极推动作用,但影响并不显著,传统贷款业务仍是决定银行收益水平的主要因素;理财业务和贷款业务过快增长都会导致银行的风险积聚,单一发展传统信贷业务并非商业银行的最优选择;中小银行理财业务对提高资产收益率的促进作用小于大型商业银行,而对增加破产风险的不利影响则要大于大型商业银行,说明大型商业银行对理财业务的成本收入控制、风险管控水平总体要高于中小银行。基于以上分析,本文最后就商业银行的理财业务提出了回归"代客"本质、注重风险管控、加强外部监管引导和规范等政策建议。 展开更多
关键词 理财业务 风险管控 回归/分析
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Variation characteristics of stable isotopes in atmospheric precipitation in Adelaide,Australia
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作者 WANG Dizhou ZHANG Xinping +2 位作者 LIU Zhongli LI Guang GUAN Huade 《地球环境学报》 CSCD 2024年第4期641-652,共12页
Background,aim,and scope Stable isotope in water could respond sensitively to the variation of environment and be reserved in different geological archives,although they are scarce in the environment.And the methods d... Background,aim,and scope Stable isotope in water could respond sensitively to the variation of environment and be reserved in different geological archives,although they are scarce in the environment.And the methods derived from the stable isotope composition of water have been widely applied in researches on hydrometeorology,weather diagnosis,and paleoclimate reconstruction,which help well for understanding the water-cycle processes in one region.Here,it is aimed to explore the temporal changes of stable isotopes in precipitation from Adelaide,Australia and determine the influencing factors at different timescales.Materials and methods Based on the isotopic data of daily precipitation over four years collected in Adelaide,Australia,the variation characteristics of dailyδD,δ^(18)O,and dexcess in precipitation and its relationship with meteorological elements were analyzed.Results The results demonstrated the local meteoric water line(LMWL)in Adelaide,wasδD=6.38×δ^(18)O+6.68,with a gradient less than 8.There is a significant negative correlation between dailyδ^(18)O and precipitation amount or relative humidity at daily timescales in both the whole year and wither/summerhalf year(p<0.001),but a significant positive correlation between dailyδ^(18)O and temperature in the whole year and the winter half-year(p<0.001).Discussion The correlation coefficients betweenδ^(18)O and daily mean temperature didn’t show a significant positive correlation,which may be attributed to that the precipitation in Adelaide area in January was mainly influenced by strong convective weather,and the stable isotope values in precipitation were significantly negative.Furthermore,this propose was also evidenced by the results from dexcess of precipitation with larger value in the winter half-year than that in the summer half-year,which may be resulted from the precipitation events in winter are mostly influenced by oceanic water vapor,while the sources of water vapor in summer precipitation events are more complicated and influenced by strong convective weather.On the other hand,the slope and intercept of theδ^(18)O—P regression lines in the summer months(-0.41 and 0.50‰)are larger and smaller than those in the winter months(-0.22 and-2.15‰),respectively,indicating that the precipitation stable isotopes have a relatively stronger rainout effect in the summer months than in the winter months.Besides,the measured values ofδ^(18)O in daily precipitation have a good linear relationship with our simulated values ofδ^(18)O,demonstrating the established regression model could provide a reliable simulation for theδ^(18)O values in daily precipitation in Adelaide area.It’s worth noting that the precipitation events with low precipitation amount,low relative humidity and high temperature,usually had relatively small slope and intercept of MWL,implying that raindrops may be strongly affected by sub-cloud secondary evaporation in the falling process.Conclusions The variation ofδ^(18)O in daily precipitation from Adelaide region was controlled by different factors at different timescales.And the water vapor sources and the meteorological conditions of precipitation events(such as the degree of sub-cloud secondary evaporation)also played an important role on the variation ofδ^(18)O.Recommendations and perspectives Stable isotope in daily precipitation can provide more accurate information about water-cycle and atmosphere circulation,it is therefore necessary to continue to collect and analyze daily-scale precipitation data over a longer time span.The results of this study will provide the basis for the fields of hydrometeorology,meteorological diagnosis and paleoclimate reconstruction in Adelaide,Australia. 展开更多
关键词 Adelaide PRECIPITATION stable isotopes meteoric water line stepwise regression analysis
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Regression Relationship between WI and FMC at Different Growth Periods of Sawtooth Oaks Leaf 被引量:2
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作者 费鲜芸 张志国 +2 位作者 卢霞 高祥伟 何润昭 《Agricultural Science & Technology》 CAS 2010年第7期49-52,共4页
[Objective] The aim was to study the regression relationship between water index (WI) and fuel moisture content (FMC) of different growth periods of sawtooth oaks leaf.[Method] Taking sawtooth oaks in Huaguo Mount... [Objective] The aim was to study the regression relationship between water index (WI) and fuel moisture content (FMC) of different growth periods of sawtooth oaks leaf.[Method] Taking sawtooth oaks in Huaguo Mountain,Lianyungang City as research object,the sensitivity of WI to leaf FMC was studied at leaf level,and statistical characteristics were analyzed.[Result] The WI of sawtooth oaks leaves was sensitive to the changes of FMC,and the line regression level between them was significant.A fitting curve between leaf FMC and WI was obtained.[Conclusion] The research provides reference for acquisition methods of vegetation water remote sensing within the range of study area. 展开更多
关键词 High spectral Fuel moisture index Water content Regression analysis Swatooth oaks leaf
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Prediction of pre-oxidation efficiency of refractory gold concentrate by ozone in ferric sulfate solution using artificial neural networks 被引量:2
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作者 李青翠 李登新 陈泉源 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期413-422,共10页
An artificial neural network model was developed to predict the oxidation of refractory gold concentrate (RGC) by ozone and ferric ions. The concentration of ozone and ferric ions, pulp density, oxygen amount, leach... An artificial neural network model was developed to predict the oxidation of refractory gold concentrate (RGC) by ozone and ferric ions. The concentration of ozone and ferric ions, pulp density, oxygen amount, leaching time and temperature were employed as inputs to the network; the output of the network was the percentage of the ferric extraction iron from RGC. The multilayered feed-forward networks were trained by 33 sets of input-output patterns using a back propagation algorithm; a three-layer network with 8 neurons in the hidden layer gave optimal results. The model gave good predictions of high correlation coefficient (R2=0.966). The predictions by ANN are more accurate when compared with conventional multivariate regression analysis (MVRA). In addition, calculation with ANN model indicates that temperature is the predominant parameter and ozone concentration is the lesser influential parameter in the pre-oxidation process of refractory gold ore. The ANN neural network model accurately estimates the ferric extraction during pretreatment process of RGC in gold smelter plants and can be used to optimize the process parameters. 展开更多
关键词 PRE-OXIDATION multivariate regression analysis artificial neural network refractory gold concentrate
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Evaluation of Chinese Cabbage Sensory Quality and Its Relationship with Contents of Main Nutrient Components 被引量:1
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作者 龚振平 于拴仓 +5 位作者 张凤兰 余阳俊 赵岫云 张德双 汪维红 苏同兵 《Agricultural Science & Technology》 CAS 2016年第7期1592-1596,共5页
In order to establish a comprehensive evaluation system for quality of Chinese cabbage, 28 Chinese cabbage cultivars or inbreeds were selected as ex- perimental materials to identify the raw and cooked taste and deter... In order to establish a comprehensive evaluation system for quality of Chinese cabbage, 28 Chinese cabbage cultivars or inbreeds were selected as ex- perimental materials to identify the raw and cooked taste and determine the nutrient component contents, and the subjective factors (taste) and objective factors (nutrient component contents) influencing the sensory quality of Chinese cabbage were ana- lyzed by multiple regression and path analysis. The results showed that two regres- sion equations were obtained: yr (raw quality)=0.310 3+0.254 0xl (juiciness)+0.176 2 x2 (sweetness)+0.221 6x3 (crispness)+0.319 9x4 (flavor); Yc (cooked quality)=0.204 4+ 0.250 9 xs (residue)+0.246 9x6 (cooked sweetness)+0.182 5x7 (softness)+0.323 lx8 (cooked flavor). The path analysis results showed that among the sensory indices, the total coefficients of sweetness and juiciness were 0.445 3 and 0.427 6, respec- tively. It indicated they were the main factors affecting the raw quality of Chinese cab- bage, followed by flavor and crispness. Sweetness, with total coefficient of 0.515 2, showed the greatest effect on the cooked quality of Chinese cabbage, followed by residue, cooked flavor and softness. The effects of nutrient component contents on the sensory quality of Chinese cabbage were further analyzed, and the regression equa- tions were obtained: y, =-32.192 0+0.389 3xw (moisture content)+1.169 8x~ (soluble sugar content); Yc = 7.497 1+0.732 6xs - 5.668 8x, (organic acid content)-2.176 3x~ (crude fiber content). The standardized regression coefficients of soluble sugar con- tent were all highest with the value of 0.580 7 in the raw quality regression equa- tion and 0.325 0 in the cooked quality one, indicating that among the six nutrient components, the soluble sugar content was the main factor affecting both raw and cooked quality of Chinese cabbage. This study will provide certain basis for quality evaluation, selection and breeding of high-quality Chinese cabbage. 展开更多
关键词 Chinese cabbage Sensory quality Nutritional component Path analysis Regression analysis
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Extraction of Soil Organic Matter Information by Multi-spectral Remote Sensing Based on Diverse Landforms 被引量:1
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作者 杨建锋 马军成 +1 位作者 王令超 樊鹏 《Agricultural Science & Technology》 CAS 2016年第7期1744-1748,共5页
Based on diverse landforms, the correlation between soil organic matter content and multi-spectral band of remote sensing image was analyzed in this pa- per. In addition, the inversion models were built for the soil o... Based on diverse landforms, the correlation between soil organic matter content and multi-spectral band of remote sensing image was analyzed in this pa- per. In addition, the inversion models were built for the soil organic matter content in different landforms. The results showed that the spectral reflectance was nega- tively related to soil organic matter content; linear regression analysis of remove was performed throughout the bands using SPSS. When the inversion models were built based on all the bands, better fitting effect was obtained. The precision of in- version models built based on different landforms was higher than those built re- gardless landforms. Compared with the actual value, the identification level of soil organic matter content was 91 65% under the allowable error was 7%. It indicated that the extraction of soil organic matter with inversion model that was built based on different landforrrs was feasible with higher precision. 展开更多
关键词 Landform type MULTI-SPECTRAL Regression analysis Soil organic matter
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Variation of the second-phase morphology and its influence on fracture behavior of Al-Si alloy 被引量:1
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作者 孙瑜 陈晋 孙国雄 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期53-58,共6页
Using an optical microscope and scanning electron microscope (SEM), the variation of eutectic Si morphology of Al-Si alloy in solution treatment was observed to study its influence on mechanical properties and fractur... Using an optical microscope and scanning electron microscope (SEM), the variation of eutectic Si morphology of Al-Si alloy in solution treatment was observed to study its influence on mechanical properties and fracture behavior. The results show that eutectic Si undergoes stubbing, necking, fragmentation, and growth in the initial stage (250 min); in the middle solution stage (250 to 400 min), the eutectic Si morphology has no significant change, only the degree of spheroidizing becomes higher; after 600 min, the growth of eutectic Si is a coarsening process controlled by diffusion and follows the Liftshitz-Slyozov-Wangner (LSW) model, and the eutectic Si morphology deteriorates due to the occurrence of facets and lap. Based on the quantitative measure and regression analysis, the eutectic Si morphology has a remarkable influence on mechanical properties and fracture behavior. 展开更多
关键词 Al-Si alloy variation of Si phase mechanical properties fracture behavior
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Influential Factors of House-purchasing Intention in Work construction Sites among Migrant Workers with a Case of Investigations on 203 Migrant Workers from Jiangxi Province 被引量:2
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作者 刘文 王彦之 《Agricultural Science & Technology》 CAS 2015年第12期2881-2885,共5页
The research selected 13 factors from individual and family characters, construction site characters and work characters and analyzed the influences on the willingness of purchasing houses on construction sites with L... The research selected 13 factors from individual and family characters, construction site characters and work characters and analyzed the influences on the willingness of purchasing houses on construction sites with Logistic regression mod- el. The results showed that gender, age differences, personality, willingness on fami- ly land conversion, management of enterprises on construction sites, relatives and friends on construction lands, and Job satisfaction were approved by significant testing, but marital status, annual household income, the rate of migrant worker in a household, transportation in work city, and corporate reputation were not approved by significant testing. 展开更多
关键词 Migrant worker House-purchasing willingness in work construction sites Influential factors Logistic regression analysis Jiangxi Province
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Physiological Changes during the Process of Pericarp Browning in the Postharvest Litchi 被引量:9
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作者 王家保 王向社 +1 位作者 徐碧玉 金志强 《Agricultural Science & Technology》 CAS 2010年第5期10-16,共7页
[Objective] Pericarp browning in the postharvest litchi significantly reduced its commercial value and limited the expanding of litchi markets. Physiological changes during the process of pericarp browning were determ... [Objective] Pericarp browning in the postharvest litchi significantly reduced its commercial value and limited the expanding of litchi markets. Physiological changes during the process of pericarp browning were determined in order to identify the underlying mechanisms. [Method] Matured Feizixiao fruits were stored at 25 ℃ and 70%±5% relative humidity. The physiological changes happened in pericarp during storage were tested at an 8-hour interval. [Result] The fruit of Feizixiao (Litchi chinensis Sonn. cv Feizixiao) turned completely brown within 72 h after being harvested under the experimental conditions. Sharp increase of the browning index occurred from 48 to 64 hours after harvest (HAH). With the browning of pericarp,water content of the whole fruit and pericarp decreased continuingly. In contrast,there were no significant changes in the water content of pulp during the same period. MDA content,pH value and relative leakage rate of pericarp were increased during storage. Most of pigment contents including anthocyanin,flavonoid,phenols,chlorophyll a and total chlorophyll decreased. POD activity was initially increased in 32 HAH and then decreased afterwards. PPO activity was decreased continuously,while the activities of catalase and superoxide dismutase exhibited the pattern of 'increasing-decreasing-increasing' as the storage time progressed. Correlation,stepwise regression and path analyses showed that water loss of pericarp was the major factor of pericarp browning. Principal and cluster analyses showed that there were two stages of pericarp browning during the course of litchi storage. [Conclusion] Water status of pericarp was the most important factor affecting pericarp browning. The pericarp browning happened by stages,which was mainly determined by the water loss of pericarp. 展开更多
关键词 Litchi (Litchi chinensis Sonn.) Pericarp browning Physiological changes Principal analysis:Cluster analysis
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Relationship between Rice Planthopper Occurrence Area in China and Atmospheric Circulation Indices 被引量:3
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作者 季璐 朱敏 《Agricultural Science & Technology》 CAS 2012年第9期2006-2011,共6页
[Objective] This study aimed to establish models based on atmospheric cir- culation indices for forecasting the area attacked by rice planthopper every year, and to provide guide for preventing and controlling plantho... [Objective] This study aimed to establish models based on atmospheric cir- culation indices for forecasting the area attacked by rice planthopper every year, and to provide guide for preventing and controlling planthopper damage. [Method] The data related to rice planthopper occurrence and atmospheric circulation were collected and analyzed with the method of stepwise regression to establish the prediction models. [Result] The factors significantly related to the area attacked by rice plan-thopper were selected. Two types of prediction models were established. One was for Sogatella furcifera (Horvath), based on Atlantic-Europe circulation pattern W in October in that year, Pacific polar vortex area index in October in that year, North America subtropical high index in August in that year, Atlantic-Europe circulation pattern W in June in that year, northern boundary of North America subtropical high in February in that year, Atlantic-Europe polar vortex intensity index in October in that year and Asia polar vortex intensity index in November in the last year; the other type of prediction models were for Nilaparvata lugens (Stal), based on the Eastern Pacific subtropical high intensity index in July in that year, northern hemi- sphere polar vortex area index in October in the last year, Asia polar vortex strength index in November in the last year, north boundary of North America-At- lantic subtropical high in September in that year, north boundary of North Africa-At- lantic-North America subtropical high in January in that year, sunspot in September of the last year and eastern Pacific subtropical high area index in September in that year. [Conclusion] With the stepwise regression, the forecasting equations of the rice planthopper occurrence established based on the atmospheric circulation indices could be used for actual forecast. 展开更多
关键词 Rice planthopper Atmospheric circulation Prediction models
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Modeling dam deformation using independent component regression method 被引量:3
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作者 戴吾蛟 刘斌 +1 位作者 丁晓利 黄大伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2194-2200,共7页
In the application of regression analysis method to model dam deformation, the ill-condition problem occurred in coefficient matrix always prevents an accurate modeling mainly due to the multicollinearity of the varia... In the application of regression analysis method to model dam deformation, the ill-condition problem occurred in coefficient matrix always prevents an accurate modeling mainly due to the multicollinearity of the variables. Independent component regression (ICR) was proposed to model the dam deformation and identify the physical origins of the deformation. Simulation experiment shows that ICR can successfully resolve the problem of ill-condition and produce a reliable deformation model. After that, the method is applied to model the deformation of the Wuqiangxi Dam in Hunan province, China. The result shows that ICR can not only accurately model the deformation of the dam, but also help to identify the physical factors that affect the deformation through the extracted independent components. 展开更多
关键词 dam deformation analysis independent component regression principal component regression ill-condition problem interpreting of dam deformation
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Nonlinear Regression Fuzzy Analysis of Real Variable and Fuzzy Parameter 被引量:1
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作者 史本广 陈守信 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期71-76,共6页
As far as the nonlinear regression method is concerned, the condition when both independent and dependent variable take the Fuzzy value, while the parameter, θ∈ΘR m the real value, have been discussed in . But for... As far as the nonlinear regression method is concerned, the condition when both independent and dependent variable take the Fuzzy value, while the parameter, θ∈ΘR m the real value, have been discussed in . But for most of actual conditions, the independent variable generally takes the real value, while both parameter and dependent variable take the Fuzzy value. This paper propounded a method for the latter and its relevant Fuzzy regreession model. In addition the Fuzzy observation, matrix distribution and the rational estimation of modeling parameter have also been discussed. Furthermore, the Max min estimation of modeling parameter and its corresponding calculating sequence have also been offered to and the calculating example shows the method is feasible. 展开更多
关键词 nonlinear regression parameter estimation matrix distribution
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Ambient Light Alters Gene Expression Pattern of Enzymes and Transcription Factors Involved in Phenylpropanoid Metabolic Pathway in Potato under Chilling Stress 被引量:1
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作者 秦玉芝 George Tai +2 位作者 谢开云 何长征 熊兴耀 《Agricultural Science & Technology》 CAS 2014年第11期1899-1904,共6页
[Objective] Expressions of key enzymatic genes involved in phenyl-propanoid metabolic pathway in potato and StR2R3-MYB and StTGA transcripters were investigated in the present study. [Method] The primitive cultivar Ya... [Objective] Expressions of key enzymatic genes involved in phenyl-propanoid metabolic pathway in potato and StR2R3-MYB and StTGA transcripters were investigated in the present study. [Method] The primitive cultivar Yan was the materials for replicated trials and total RNA extracted from tissues of seedlings. Re-al-time florescent quantification PCR, multiple intervals of air temperature, light-il umi-nation and time-duration were factors of treatments in the experiment. Data on gene expressions were obtained and proceed to asses and compare effects based on statistical analysis. [Result] The results showed negative correlations between tem-perature degrees and expressions of StPAL, StDFR and StR2R3-MYB genes but not StTGA. Positive correlations, however, were derived between those of StCHS, StDFR and StR2R3-MYB and light-intensity. Significant interactive effects between expressions of StPAL and StDFR and treatments, light intensity and temperature degree, along the phenylpropanoid pathway were observed. Transcription regulator of StR2R3-MYB showed significant positive effect on the expression of StCHS of potato. StTGA transcription factor, on the other hand, gave significant negative ef-fects on the expression of StDFR. [Conclusion] Results from present study reveal the role of environmental factors and complicate interactions between such condi-tions as temperature-light il umination and mRNA function of target genes. 展开更多
关键词 Potato Light Low temperature Genes related to phenylpropanoid metabolic pathway Regression analysis
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Application of cluster analysis and stepwise regression in predicting the traffic volume of lanes 被引量:5
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作者 张赫 王炜 顾怀中 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期359-362,共4页
Because of the difficulty to obtain the traffic flow information of lanes at non-detector intersections in most metropolises of the world,based on the relationships between the lanes of signal-controlled intersections... Because of the difficulty to obtain the traffic flow information of lanes at non-detector intersections in most metropolises of the world,based on the relationships between the lanes of signal-controlled intersections,cluster analysis and stepwise regression are integrated to predict the traffic volume of lanes at non-detector isolated controlled intersections.First cluster analysis is used to cluster the lanes of non-detector isolated signal-controlled intersections and the lanes of all signal-controlled intersections with detectors.Then, by the results of cluster analysis,the traffic volume samples are selected randomly and stepwise regression is used to predict the traffic volume of lanes at non-detector isolated signal-controlled intersections.The method is tested by the traffic volume data of lanes of the road network of Nanjing city.The problem of predicting the traffic volume of lanes at non-detector isolated signal-controlled intersections was resolved and can be widely used in urban traffic flow guidance and urban traffic control in cities without enough intersections equipped with detectors. 展开更多
关键词 intelligent transportation systems (ITS) cluster analysis stepwise regression
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EMPIRICAL STUDY ON CAPITAL STRUCTURE OF LISTED COMPANIES IN CHINESE STOCK MARKET 被引量:1
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作者 郝丽萍 谭庆美 《Transactions of Tianjin University》 EI CAS 2001年第3期172-177,共6页
Capital structure decision is an important issue of corporate finance.Theories show that,the corporate debt ratio is determined by many factors.This study conducts empirical work on capital structure theories,focusing... Capital structure decision is an important issue of corporate finance.Theories show that,the corporate debt ratio is determined by many factors.This study conducts empirical work on capital structure theories,focusing on the corporate data of Chinese listed companies,by considering the intrinsic characteristics,utilizing the principal factor analysis and the ridge regression method.Our results suggest that a firms debt ratio has a positive relationship with its size,profitability and operating risk and has a negative relationship with its growth and non debt tax shield,while the long term leverage has a positive relationship with its collateral value of assets. 展开更多
关键词 capital structure empirical study factor analysis ridge regression
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Analyses of unified congestion measures for interrupted traffic flow on urban roads 被引量:1
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作者 任刚 范超 +2 位作者 华璟怡 黄正锋 吴建波 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期101-106,共6页
To study the congestion of interrupted flow on urban roads, a comprehensive evaluation method is proposed. First, based on the results of correlation analysis between different parameters of interrupted flow, the traf... To study the congestion of interrupted flow on urban roads, a comprehensive evaluation method is proposed. First, based on the results of correlation analysis between different parameters of interrupted flow, the traffic parameters of interrupted traffic flow are divided into two categories: the basic parameters and the operation parameters. Polynomial regression is used to formulize the nonlinear relationships between the basic parameters and the operation parameters. Then, the congestion model incorporating both operational and volume characteristics of traffic flow is proposed. The inputs of the model are the basic parameters, while the output is a dimensionless index value between 0 and 1. Finally, the proposed methods are compared with existing evaluation measures of congestion. Results show that the proposed indices can capture the variation of both the basic parameters and the operation parameters, which is more balanced compared with the existing evaluation measures. 展开更多
关键词 interrupted flow correlation analysis polynomial regression comprehensive congestion model
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Research on the Process of Yield Formation Based on Dynamic Design in Winter Wheat
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作者 张竹琴 周顺利 +2 位作者 乔嘉 赵姣 廖树华 《Agricultural Science & Technology》 CAS 2010年第4期6-9,109,共5页
[Objective]The aim was to research on construction of yield formation model of winter wheat.[Method]In the case of variety Shijiazhuang 8,the process of yield trait formation was studied by the dynamic ideal and unifo... [Objective]The aim was to research on construction of yield formation model of winter wheat.[Method]In the case of variety Shijiazhuang 8,the process of yield trait formation was studied by the dynamic ideal and uniform experimental design;the differences between plant dry weight and population indexes were analyzed by using multiple comparison analysis,and the yield formation model was developed by multiple regression analysis.[Result]The results showed that multiple correlation coefficients of yield formation model ranged from 0.91 to 0.97.[Conclusion]The model was significant which provide certain theoretical base for high yield and high efficiency cultivation of winter wheat. 展开更多
关键词 Dynamic test Uniform experimental design Regression analysis Grain yieldf
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New Math Model for Designing Engine Radiator
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作者 黄虹宾 刘淑艳 +1 位作者 郑世琴 阎为革 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期141-146,共6页
Aim To raise the H-NE math model for designing engine radiators.Methods Thismodel was founded on multi-nonlinear regression technology,and the quadratic equatingmethod was used to smooth original data.Through the sens... Aim To raise the H-NE math model for designing engine radiators.Methods Thismodel was founded on multi-nonlinear regression technology,and the quadratic equatingmethod was used to smooth original data.Through the sensitivity analysis about radiatoroptimization designing,some major restraints were obtained.Results Type 1301C radiator wasoptimizingly renwed by use o this model,and the new radiator is more excellent than theold one in respect of the heat transfer factor and the manufacturing cost.Conclusion Theradiation performance can be improved,the area can be reduced,and the fitting scope can bewidened if this model is used in designing radiators. 展开更多
关键词 radiator performance multi-nonlinear regression analysis optimizing design
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Material Design and Experimental Analysis of a New Type of Semiconductor ER Fluids
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作者 朱石沙 魏宸官 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期155-159,共5页
To improve the electrorheological effect of electrorheological fluid (ERF), a new type of the electrosensitive particle material, polynaphthalene quinone was prepared, whose molecules contain blended atoms of nitrogen... To improve the electrorheological effect of electrorheological fluid (ERF), a new type of the electrosensitive particle material, polynaphthalene quinone was prepared, whose molecules contain blended atoms of nitrogen, oxygen, sulphur and big π bond conjugate system. In both DC and AC electric fields, the ERF material showed a distinct ER effect. Especially, in the alternating electric field, the shear stress of this material versus AC voltage has a better quadratic relation than that of the other materials. The experimental data showed that organic semiconductor polymers with big π bond conjugate system are a new type of electrosensitive particle materials which are worth well developing. 展开更多
关键词 electrorheological fluid(ERF) alternating electric field regression analysis
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Correlation Analysis of SPAD Value with Chlorophyll Content and Economic Yield Traits of Brassica napus L. 被引量:6
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作者 高建芹 浦惠明 +4 位作者 张洁夫 龙卫华 陈锋 周晓婴 张维 《Agricultural Science & Technology》 CAS 2013年第10期1421-1428,共8页
[Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish reg... [Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish regression functions. [Method] Based on 34 Brassica napus L. varieties, SPAD value, chlorophyll content, agronomic characters, economic characters and yield traits were measured and re- gression functions were established according to correlations. [Result] SPAD value, chlorophyll content, agronomic and economic characters and yield traits all achieved significant level in differences among 34 varieties. Specifically, SPAD value was of extremely significant correlation with chlorophyll a and b, total chlorophyll and carotenoid, and the correlation from high to low was chl-b〉chl-z〉chl-a〉chl-x. SPAD value was of significantly positive correlation with total pod number per plant, plant height, seed number per pod, yield per plant and harvest yield, and of insignificant correlation with branch point height, effective branch number, pod density of main stem, and pod length. [Conclusion] It is simple and rapid to predict chlorophyll con- tent, economic characters and yields of Brassica napus L. with SPAD value and re- gression functions. 展开更多
关键词 Brassica napus L. SPAD value Chlorophyll content Economic yield Correlation analysis
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