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Agricultural Policy, Climate Factors and Grain Output: Evidence From Household Survey Data in Rural China 被引量:15
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作者 CHEN Yong-fu WU Zhi-gang +3 位作者 ZHU Tie-hui YANG Lei MAGuo-ying Chien Hsiao-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第1期169-183,共15页
This paper estimates a stochastic frontier function using a panel data set that includes 4 961 farmer households for the period of 2005-2009 to decompose the growth of grain production and the total factor productivi... This paper estimates a stochastic frontier function using a panel data set that includes 4 961 farmer households for the period of 2005-2009 to decompose the growth of grain production and the total factor productivity (TFP) growth at the farmer level. The empirical results show that the major contributor to the grain output growth for farmers is input growth and that its average contribution accounts for 60.92% of farmer’s grain production growth in the period of 2006-2009, whereas the average contributions sourced from TFP growth and residuals are only 17.30 and 21.78%, respectively. The growth of intermediate inputs is a top contributor with an average contribution of 44.46%, followed by the planted area (18.16%), investment in fixed assets (1.05%), and labor input (-2.75%), indicating that the contribution from the farmer’s input growth is mainly due to the growth of intermediate inputs and that the decline in labor inputs has become an obstacle for farmers in seeking grain output growth. Among the elements consisting of TFP growth, the contribution of technical progress is the largest (32.04%), followed by grain subsidies (8.55%), the average monthly temperature (4.26%), the average monthly precipitation (-0.88%), the adjusted scale effect (-5.66%), and growth in technical efficiency (-21.01%). In general, the contribution of climate factors and agricultural policy factor are positive and significant. 展开更多
关键词 decomposition of grain output growth total factor productivity (TFP) stochastic frontier production function Chinese farmer households
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Weight Determining of Factors Influencing Grain Output Based on Entropy Weight Method 被引量:3
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作者 LI Jun Department of Management,Xijing University,Xi’an 710123,China 《Asian Agricultural Research》 2012年第3期7-9,共3页
This article selects 8 main factors(the number of rural employees,total power of agricultural machinery,effective irrigation area of crops,growing area of grain crops,fertilizer consumption,electricity consumption in ... This article selects 8 main factors(the number of rural employees,total power of agricultural machinery,effective irrigation area of crops,growing area of grain crops,fertilizer consumption,electricity consumption in rural areas,area affected and area covered) as the factors influencing grain output,and offers the method of determining weight of factors influencing grain output using entropy weight method.According to the relevant data in the period 1985-2005,we analyze the weight of factors influencing grain output in China by example.The results show that the electricity consumption in rural areas has the greatest impact on grain output,followed by total power of agricultural machinery,fertilizer consumption and area covered.To increase grain output,we must enhance the degree of mechanization,free people from the former process of direct cultivation,strengthen water conservancy construction,and do a good job in disaster prevention and mitigation. 展开更多
关键词 GRAIN output ENTROPY WEIGHT method factors WEIGHT
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Measurement and Comparison of Output Factors Using Two Detectors for NOVAC7 IntraOperative Radiotherapy Accelerator 被引量:1
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作者 Md Rafiqul Islam Hiroshi Watabe Andreoli Stefano 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2020年第2期52-61,共10页
The aim of this work was to evaluate and compare the performance of comparatively new synthetic PTW 60019 microDiamond with PTW 60017 Diode E detector in measuring the output factors (OF) of IntraOperative Radiation T... The aim of this work was to evaluate and compare the performance of comparatively new synthetic PTW 60019 microDiamond with PTW 60017 Diode E detector in measuring the output factors (OF) of IntraOperative Radiation Therapy (IORT) electron beams. For a given electron beam, OFs are defined as the ratio of the dose for any applicator size at the depth of maximum to that for a reference applicator. IORT is an innovative treatment technique that delivers a large single fraction of radiation dose to the tumor bed during surgery. The electron beams considered in this study were generated by the mobile NOVAC7 system. This device produces high-dose-per-pulse electron beams with four different energies in the range from 3 MeV to 9 MeV. We performed measurements for two higher energies, namely 7MeV and 9 MeV. The beam collimation was performed through Perspex (PMMA) cylindrical applicators with different diameters. The accurate dose delivery of IORT tightly depends on the precision of measured dose by reference applicator and the output factors of clinical applicators. The output factors were measured using microDiamond and Diode E detectors. The microDiamond detector performance was compared with a Diode E detector. Determined output factors of two detectors were in good agreement. The maximum deviations of output factors for microDiamond were found 2.74%, and 2.17% for 7 MeV and 9 MeV, respectively with respect to the PTW Diode E. The microDiamond detector was shown to exhibit excellent properties for output factor measurements and could be considered as a suitable tool for electron beam dosimetry. 展开更多
关键词 INTRAOPERATIVE Radiation THERAPY (IORT) NOVAC7 Detectors output factorS
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Measurement and Analysis of PDDs Profile and Output Factors for Small Field Sizes by cc13 and Micro-Chamber cc01 被引量:1
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作者 Muhammad Kamran Rasheed Nasir Nauman Amjad +1 位作者 Aasia Razzaq Tariq Siddique 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第1期36-56,共21页
Small radiation fields are abundantly used in modern radiotherapy techniques like in IMRT and SRS. In order to commission these techniques, dosimetric data for small fields is required. The purpose of this study is to... Small radiation fields are abundantly used in modern radiotherapy techniques like in IMRT and SRS. In order to commission these techniques, dosimetric data for small fields is required. The purpose of this study is to compare dosimetric measurements with two different ion chambers cc13, and cc01 for smaller fields. Dosimetric measurements are beam profile, output factor, pdds, and collimator factor. Dosimetric data is acquired in water phantom for two different photon beam energies 6 MV and 15 MV with zero gantry angle. In beam profiles cc13 chamber, measure wider penumbra as compare to cc01. And this wider measurement of penumbra occurs for smaller as well as for larger field sizes. Accumulated relative error in the measurement of penumbra for number of field sizes and 6 MV at dmax, and at 10 cm depth are 34.32% and 27.72% respectively. Accumulated relative error in the measurement of penumbra for number of field sizes and 15 MV at dmax, and at 10 cm depth are 28.49% and 23.92%. In case of output factor for smaller fields cc13 underestimates the output factor relative to cc01, with non-linear increase for smaller fields. But for larger fields, this increase in output factor is almost linear difference of two chambers is decreased. For very smaller fields × 2 cm, relative error in output factor of cc13 and cc01 is greater than 5% and rapidly increases with decreasing field size. But for lager fields, this relative error is negligible. In measurement of pdds after the buildup region difference occurs in the response of two chambers cc13 and cc01 for smaller fields. For field sizes ≤2 cm × 2 cm average cc13-cc01 at various depths 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, and 80 cm is almost greater than 0.5 cm. And similarly as output factor, this difference (cc13-cc01) increases with field size decreasing. 展开更多
关键词 PERCENTAGE Depth Dose PDD Intensity Modulation Radiotherapy IMRT STEREOTACTIC Radio Surgery SRS Measurement of output factor SCP
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The Impact of Small Field’s Off-Set on Output Factor in Intensity Modulated Radiation Treatment
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作者 Hulya Ozdemir Nina Tuncel Adem Unal Kizildag 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第4期433-444,共12页
In intensity modulated radiation treatment (IMRT) planning, the use of asymmetrically collimated fields that are placed on central axis or its off-set is mostly required. Output is the main topic discussed today for e... In intensity modulated radiation treatment (IMRT) planning, the use of asymmetrically collimated fields that are placed on central axis or its off-set is mostly required. Output is the main topic discussed today for extremely small and/or severe irregularly shaped fields. The air scatter data are involved directly or indirectly in obtaining the output. Despite the fact that extensive data have been published in many studies to provide a guide on the magnitude of output factor for clinical accelerators, there are very few data reviewed about output factor in-air or phantom for off-set fields. This study was aimed to investigate the impact of these conditions for small fields. This study was conducted in Elekta Synergy linear accelerator which produces 6 MV X-ray energy. The in-air output factor (Sc) has been measured by CC04 ion chamber with brass-alloy “build-up” cap and Dose-1 electrometer, and the total output (Scp) measurements were carried on at dose maximum depth in phantom by the same chamber and Thermoluminescence dosimeter (TLD) for 1 - 10 cm2 fields. The all measurements at center of isocenter and off-set fields at three directions (X2, Y1, Diagonal) were done. By decreasing field size from 10 to 2 cm2 at isocenter, the Sc value using CC04 was decreased to 5.4% and Scp using CC04 and TLD to 14.5% and 11% respectively. By increasing off-set value, the Sc and Scp values were increased in all directions comparing to central fields. The maximum increase was obtained in Y1 direction for Sc and Scp. TLD results for Scp is slightly higher than CC04. The dosimetric properties of small fields and their off-set should be evaluated and modelled appropriately in the treatment planning system to ensure accurate dose calculation in Intensity Modulated Radiation Treatment. 展开更多
关键词 Small Field Off-Set FIELDS Total output factor In-Air output factor Intensity MODULATED Radiation Treatment
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质子累积辐照效应对CMOS图像传感器饱和输出的影响
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作者 彭治钢 白豪杰 +5 位作者 刘方 李洋 何欢 李培 贺朝会 李永宏 《物理学报》 北大核心 2025年第2期137-148,共12页
本文通过辐照实验和TCAD仿真,研究了质子累积辐照导致四晶体管钳位光电二极管(4T PPD)CMOS图像传感器的饱和输出变化机理.实验采用的质子能量为12 MeV和60 MeV,最高质子注量为2×10^(12)cm^(-2).实验结果表明:12 MeV和60 MeV质子最... 本文通过辐照实验和TCAD仿真,研究了质子累积辐照导致四晶体管钳位光电二极管(4T PPD)CMOS图像传感器的饱和输出变化机理.实验采用的质子能量为12 MeV和60 MeV,最高质子注量为2×10^(12)cm^(-2).实验结果表明:12 MeV和60 MeV质子最高注量辐照后分别导致转换增益增大8.2%和7.3%,满阱容量分别减小7.3%和3.8%.饱和输出在12 MeV质子辐照下变化趋势不显著,在60 MeV质子辐照下增大3%.在TCAD仿真中,建立了单个三维4T PPD像元模型,开展了质子累积辐照效应仿真来分析损伤机理.仿真结果表明像元饱和输出的变化由满阱容量、复位晶体管的物理特性和浮置扩散区的电容决定,但它们具有不同的影响.具体而言,满阱容量的降低导致饱和输出减小,而复位晶体管的辐照效应导致饱和输出增大.辐照导致浮置扩散区的电容减小,从而使转换增益增大,进而饱和输出增大.上述工作较为全面地揭示和分析了辐照后饱和输出的变化机理,研究成果对CMOS图像传感器的辐射损伤分析具有一定的指导意义. 展开更多
关键词 CMOS图像传感器 总剂量效应 饱和输出 满阱容量 转换增益
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Agricultural Development of Nanjing Suburban Counties based on Contribution Models of Production Factors
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作者 李响 张琤琤 +1 位作者 李睿婷 许才明 《Agricultural Science & Technology》 CAS 2012年第12期2663-2666,共4页
According to data in Nanjing Statistical Yearbook, contribution made by agricultural production factors was analyzed with contribution models of agricultural factors and the results showed that with restriction of lab... According to data in Nanjing Statistical Yearbook, contribution made by agricultural production factors was analyzed with contribution models of agricultural factors and the results showed that with restriction of labor force and land, Nanjing suburban counties have entered into a stage of "high input-high output", considering no matter from agricultural total value of output or from agricultural added value. In future, structure configuration of agricultural input factors should be optimized in Nanjing suburban counties by technology input to improve agricultural technology and technical efficiency in order to further achieve sustainable development of agriculture. 展开更多
关键词 Nanjing suburban counties Agricultural output Input factors Contribution analysis
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Agricultural Input and Output in Jiangsu Province with Case Analysis
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作者 杜华章 《Agricultural Science & Technology》 CAS 2014年第11期2006-2010,2025,共6页
[Objective] The aim was to explore interrelationship between agricultural input and output in Jiangsu and the influence degrees of input factors on agricultur-al output. [Method] Quantitative analysis and evaluation w... [Objective] The aim was to explore interrelationship between agricultural input and output in Jiangsu and the influence degrees of input factors on agricultur-al output. [Method] Quantitative analysis and evaluation were made on agricultural input and output in Jiangsu during 1990-2012 as per factor analysis and regression analysis. [Result] The result of factor analysis showed that since the 1990s, the comprehensive efficiency of agricultural input/output in Jiangsu was growing and in-put/output of agriculture, forestry, animal husbandry and fishery, crop farming, and of food production were extracted, whose scores reflect the changes of input/output ef-ficiencies in terms of agriculture, forestry, animal husbandry, fishery, crop farming and food production in the two decades. The results of regression analysis indicated that the effects of the three indices on agricultural output tended to be volatile and the influence degrees were concluded also by regression parameters. [Conclusion] The research provides theoretical references for agricultural input/output structure in Jiangsu Province. 展开更多
关键词 Agriculture Input/output factor analysis Regression analysis Jiangsu Province
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Iterative identification of output error model for industrial processes with time delay subject to colored noise 被引量:1
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作者 董世健 刘涛 +1 位作者 李明忠 曹毅 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期2005-2012,共8页
To deal with colored noise and unexpected load disturbance in identification of industrial processes with time delay, a bias-eliminated iterative least-squares(ILS) identification method is proposed in this paper to e... To deal with colored noise and unexpected load disturbance in identification of industrial processes with time delay, a bias-eliminated iterative least-squares(ILS) identification method is proposed in this paper to estimate the output error model parameters and time delay simultaneously. An extended observation vector is constructed to establish an ILS identification algorithm. Moreover, a variable forgetting factor is introduced to enhance the convergence rate of parameter estimation. For consistent estimation, an instrumental variable method is given to deal with the colored noise. The convergence and upper bound error of parameter estimation are analyzed. Two illustrative examples are used to show the effectiveness and merits of the proposed method. 展开更多
关键词 Time delay system output error model Recursive least-squares Instrumental variable Variable forgetting factor
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Assessment of Factors That Affect the Performance of Agricultural Production, in the Case of Amhara Region, Ethiopia
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作者 Melkamu Ayana Zeru 《Agricultural Sciences》 2018年第8期1058-1069,共12页
The agricultural sector is the basis of livelihood for a large proportion of society in Ethiopia. In the three political regimes in modern Ethiopia, the Imperial, the military and the Ethiopian people revolutionary de... The agricultural sector is the basis of livelihood for a large proportion of society in Ethiopia. In the three political regimes in modern Ethiopia, the Imperial, the military and the Ethiopian people revolutionary democratic front (EPRDF), agriculture has been regarded as a critical sector. The Agricultural Development Led Industrialization (ADLI) is the national policy of the country. Regardless of the government policy attention and investment, there is a long way to go for smallholders to ensure food self-sufficiency. Agriculture is the base of our food, transformation to industrialization, climatic change control system. Agriculture is the soul of our sovereignty for development as well as poverty reduction for individuals and country level. In Ethiopia, population density is high and has been increasing and agricultural land has been decreasing because of fragmenting or converting it into residential plots. To meet the domestic food requirements, use of improved production technologies developed by research is come out to be important. Therefore, the goal of this study was to analyze factors that affect the performance of agricultural products in Amahara region national state and to determine the highly significant input factors for producing high and qualified agricultural outputs. Data regarding total agricultural outputs and its input factors in study area of Amahara region from 2010 to 2018 was obtained from Amhara national state branch of the Ethiopian institute of agricultural sector. Correlation analyses were used to examine the strength of the relationship between each of the determinant factors with total agricultural output, while multiple regression analysis was employed to examine the simultaneous effects of several independent variables on the dependent variable, total agricultural outputs. These analyses were employed through the packages R and Stata to achieve the main objectives of the study. All of the independent variables were highly correlated with the total agricultural output. The overall regression model was highly significant (p-value < 0.01) with F = 45.532. The R-squared value implies that 93.8% percent of the changes in average total agricultural outputs are successfully explained by the variables used in the model of this study. If we take model size into account, 91.8% percent of the variation in average total agricultural output was explained by the values of the independent variables. Specifically, among the independent variables irrigated land, fertilizer, improved seed and pesticides are the most significant factors for total products (p-value < 0.05). 展开更多
关键词 AGRICULTURE ASSESSMENT TOTAL output DETERMINANT factorS
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New Index for Quantifying an Individual's Scientific Research Output
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作者 Mahmoud Abdel-Aty 《Computer Technology and Application》 2014年第1期44-50,共7页
Classifying researchers' work according to the quality of their publications rather than the quantity of their publications is an important issue. To this end we introduce a new measure, the "percentage range" or A... Classifying researchers' work according to the quality of their publications rather than the quantity of their publications is an important issue. To this end we introduce a new measure, the "percentage range" or A-index, which provides a qualitative evaluation of a researchers' productivity. The percentage range depends to a great extent on the number of single-author published papers and their citations. It is to be a new index to be considered along with the h-index. The combined factors have the advantage of making clearer the innovation of the individual authors. The resultant percentage range gives a reduced impact on its numerical value for authors who gain citations by adding their names on multi-author papers. It is shown that various dimensions of ethical integrity and originality are clarified by the new index. The important scenarios arising from this analysis are demonstrated with examples, The great differences between the new percentage range and old h-index come from the percentage range's emphasis on considering the whole work of an author, including the significance of the author's single-author papers as opposed to multiple-author contributions. This emphasis is demonstrated. 展开更多
关键词 H-INDEX impact factor research output.
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STUDY ON MAJOR FACTORS INFLUENCINGSPONTANEOUS COMBUSTION OF COAL 被引量:3
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作者 邓军 徐精彩 张辛亥 《Journal of Coal Science & Engineering(China)》 2000年第1期45-51,共7页
This paper theoretically analyzes major factors influencing spontaneous combustion of coal, such as molecule structure of coal, porosity, temperature, concentration of oxygen, coal thickness, velocity of face advance,... This paper theoretically analyzes major factors influencing spontaneous combustion of coal, such as molecule structure of coal, porosity, temperature, concentration of oxygen, coal thickness, velocity of face advance, and so on; and probes into how they affect the process of spontaneous combustion of coal, which is of momentous significance to predict or control self ignition of coal. 展开更多
关键词 COAL spontaneous combustion factors of influencing spontaneous combustion heat output
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Factors Affecting the Ratio of Service Industry in GDP: A Comparative Analysis of China, Japan, and South Korea
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作者 胡翠 许召元 《China Economist》 2012年第4期105-116,共12页
Based on the input-output model and using a demand side approach, this paper surveys how factors such as consumption, investment, net export, intermediate input and price affect the ratio of China's service industry ... Based on the input-output model and using a demand side approach, this paper surveys how factors such as consumption, investment, net export, intermediate input and price affect the ratio of China's service industry as compared with Japan and South Korea. An analysis of China's data indicates that price and residential consumption structure are key contributing factors to the rising ratio of the service industry. Conversely, intermediate input and government consumption are factors that lead to a decrease in the ratio of the service industry. An analysis of Japan and South Korea shows that price and residential consumption structures were linked to the rises in their service industry. This paper concludes that the ratio of China's service industry to gross domestic product (GDP) will continue to rise over the 12th Five-Year Plan period (2011-2015) and beyond. 展开更多
关键词 input and output service industry ratio factor
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A High Power Factor Rectifier Based on Buck Converter Operating in Discontinuous Inductor Current Mode
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作者 Jianbo Yang Weiping Zhang +1 位作者 Faris Al-Naemi Xiaoping Chen 《Energy and Power Engineering》 2013年第4期842-849,共8页
By adding a suitable LC filter to the input of a Buck converter, a high-power-factor buck converter is proposed. The converter can operate in the discontinuous-output-current mode operation. A Buck converter in this o... By adding a suitable LC filter to the input of a Buck converter, a high-power-factor buck converter is proposed. The converter can operate in the discontinuous-output-current mode operation. A Buck converter in this operation mode features simple control as the constant duty cycle PWM used. The operation condition of the converter is studied. The validity of analysis is verified by Simulation and Experimental results. 展开更多
关键词 Discontinuous-output-current BUCK Converter Power factor Correction
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Analysis of the Contribution of Total Factor Productivity to Agricultural Yield in Anhui Province
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作者 XIA Yan-lei Department of Economic Management,Chuzhou University,Chuzhou 239012,China 《Asian Agricultural Research》 2011年第5期19-21,共3页
By analyzing data concerning agricultural development from 1981 to 2010 in Anhui Province,the total factor productivity and growth rate of agriculture from 1981 to 2010 are estimated empirically.By dividing years from... By analyzing data concerning agricultural development from 1981 to 2010 in Anhui Province,the total factor productivity and growth rate of agriculture from 1981 to 2010 are estimated empirically.By dividing years from 1981 to 2010 into several subintervals,this paper evaluates and analyzes initial stage of reform and opening up,soft landing stage,the stage of financial crisis,the stage of subprime mortgage crisis and the impact of all factors on total factor growth rate of agriculture.Then it analyzes the contribution of growth of total factor productivity to total yield of agricultural economy.The research finds that the growth of total factor productivity in Anhui Province is significant to agricultural development. 展开更多
关键词 Total factor PRODUCTIVITY of AGRICULTURE Elasticit
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A Study on Input-Output Efficiency of Citrus in Jiangxi Province
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作者 Yu ZHONG 《Asian Agricultural Research》 2018年第1期10-15,共6页
This paper analyzes the citrus input-output efficiency by using the DEA-Malmquist productivity index methods based on the data of six counties in Jiangxi Province from 2010 to 2013.The result shows that TFP of Jiangxi... This paper analyzes the citrus input-output efficiency by using the DEA-Malmquist productivity index methods based on the data of six counties in Jiangxi Province from 2010 to 2013.The result shows that TFP of Jiangxi citrus is at low level overall,but the development is rapid.Technological progress is the driving force to promote productivity growth.Based on the static analysis study of six counties in 2013,it is found that the available input factors on the whole are in an ideal condition,and the citrus input factors in a few counties are redundant.Therefore,according to the results,the following policy recommendations are proposed:speeding up the intensive production of citrus in Jiangxi Province,to maximize the scale effect;adjusting the input ratio of various factors of production,so as to improve the citrus input-output efficiency. 展开更多
关键词 Input-output efficiency Total factor productivity Citrus industry Technological progress
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数字化转型对企业全要素生产率的影响——基于产业链关联视角 被引量:1
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作者 张虎 邹媛媛 高子桓 《统计与决策》 CSSCI 北大核心 2024年第13期165-170,共6页
文章选取上市公司年报以及投入产出表的相关数据,通过面板数据模型考察数字化转型对企业全要素生产率的影响效应及其作用机制。结果表明:数字化转型能够提升企业全要素生产率,并且在缓解内生性问题和进行一系列稳健性检验后结论依然成立... 文章选取上市公司年报以及投入产出表的相关数据,通过面板数据模型考察数字化转型对企业全要素生产率的影响效应及其作用机制。结果表明:数字化转型能够提升企业全要素生产率,并且在缓解内生性问题和进行一系列稳健性检验后结论依然成立;数字化转型能够通过前向关联、后向关联两种渠道来增强产业链关联的创新效应和结构效应,进而促进企业全要素生产率增长;数字化转型对企业全要素生产率增长的促进作用存在行业异质性,在劳动密集型和竞争性行业的作用效果更为明显。 展开更多
关键词 数字化转型 全要素生产率 产业链关联 投入产出表
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产业数字化如何走“实”向“深”?——数字要素全产业链溢出的内在逻辑与测算实践 被引量:1
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作者 马晓君 宋嫣琦 +1 位作者 于渊博 徐晓晴 《统计研究》 CSSCI 北大核心 2024年第7期29-47,共19页
随着数字技术的持续更新迭代,数字服务逐步推进生产管理模式向平台化、系统化变革,促使产业数字化向“技术+服务”融合赋能的模式演变。本文将产业数字化解构为数字要素的产业间价值溢出过程,运用投入产出技术定量测算数字要素溢出程度... 随着数字技术的持续更新迭代,数字服务逐步推进生产管理模式向平台化、系统化变革,促使产业数字化向“技术+服务”融合赋能的模式演变。本文将产业数字化解构为数字要素的产业间价值溢出过程,运用投入产出技术定量测算数字要素溢出程度及驱动因素,从而基于技术、服务双维度探究数字要素赋能产业升级的内在机制,为推动现代化产业体系建设提供理论参考。研究发现,数字技术通过替代并协同传统技术推进产业升级,而数字服务通过优化中间环节进入再生产过程,实现跨部门的协同共享与资源整合,延长并创新产业链条,提升全产业链经济效率。目前国民经济各主要部门基本转向服务主导的数字化转型阶段,产业间价值联动能力显著增强,全产业数字化增量转型的链式特征逐步显现。同时,数字技术溢出受数字创新效应驱动并通过产业自主数字创新延续,数字服务溢出受需求拉动效应影响,产业间流转缓慢,产业数字化内生动力仍待开发。 展开更多
关键词 产业数字化 数字要素 价值溢出 产业链 投入产出技术
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疫情后深圳市生活垃圾产生量的预测及变化分析 被引量:2
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作者 唐圣钧 侯斌 《环境卫生工程》 2024年第1期94-98,共5页
疫情后针对生活垃圾产生量的变化,开展预测并对结果进行分析,是地方政府科学制定相关规划、合理布局环卫设施建设的重要依据。因此,立足深圳市疫情前后数据,结合灰色关联度模型、多元线性回归等方法,分析2022—2035年生活垃圾产生量预... 疫情后针对生活垃圾产生量的变化,开展预测并对结果进行分析,是地方政府科学制定相关规划、合理布局环卫设施建设的重要依据。因此,立足深圳市疫情前后数据,结合灰色关联度模型、多元线性回归等方法,分析2022—2035年生活垃圾产生量预测值的变化。结果表明,生活垃圾产生量保持逐年增长趋势,规划期末水平年(2035年)的具体数值有一定程度调整。预测到2035年的生活垃圾产生量为45 547 t/d,其中再生资源回收量为14 576 t/d,生活垃圾处理处置量为30 971 t/d。建议各项环卫设施建设可灵活调整设施规模及建设周期,提升城市垃圾处理效能。 展开更多
关键词 生活垃圾 产生量 多因素分析 灰色模型预测 多元线性回归预测
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农户种植饲草料投入产出及种植行为影响因素研究——以内蒙古巴彦淖尔市杭锦后旗和磴口县为例
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作者 乌云花 永梅 +1 位作者 吕月 许黎莉 《中国农机化学报》 北大核心 2024年第7期276-281,290,共7页
国内消费结构及农业结构调整背景下,中国畜牧业迅速发展,饲草料需求不断增加,但是国内饲草料供应不足、安全问题凸显。在“粮改饲”试点旗县进行实地调研,了解当地农户饲草料种植的投入产出情况,利用Logit、2SLS及LIML模型对农户种植饲... 国内消费结构及农业结构调整背景下,中国畜牧业迅速发展,饲草料需求不断增加,但是国内饲草料供应不足、安全问题凸显。在“粮改饲”试点旗县进行实地调研,了解当地农户饲草料种植的投入产出情况,利用Logit、2SLS及LIML模型对农户种植饲草料行为的影响因素进行实证研究。结果显示,调查区域农户种植的饲草料主要以青贮玉米、苜蓿及燕麦草为主,种植苜蓿草的经济效益比其他饲草料高,2021年苜蓿草纯收益可达22 005元/hm^(2),比青贮玉米和燕麦草分别高出4 590元/hm^(2)元和12 180元/hm^(2),但是农户种植饲草料尤其苜蓿草的积极性并不高。探究农户选择种植饲草料行为的影响因素,发现政策激励、土地禀赋及组织制度因素对农户饲草料种植行为有显著的正向影响,提出政府应该尽快建立完善的土地流转市场体系,助力农户扩大种植规模,顺利进行种植业结构调整,加大饲草料种植面积,促进为养而种的良性循环,解决养殖业饲草料短缺问题以及鼓励各类合作社发挥合作制度优势,帮助农户降低种植饲草料的投入成本,拓宽饲草料的销售渠道,增加农民收入的对策建议。 展开更多
关键词 饲草料 投入产出 农户行为 影响因素 计量模型
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