[Objective]The aim was to study heterosis of N use efficiency for grain production (NUEg) of Brassica napus L. and provide theoretical basis for breeding N-efficient cultivars. [Method]Dry matter production and N co...[Objective]The aim was to study heterosis of N use efficiency for grain production (NUEg) of Brassica napus L. and provide theoretical basis for breeding N-efficient cultivars. [Method]Dry matter production and N content of six B.napus parents (Zheshuang 3,Yangyou 7,ZJ1,Shilijia,Ningyou 14 and Huyou 16) and their F1 combinations from 6 × 6 complete diallel cross in maturity stage under two N levels were measured; heterosis of NUEg,combining ability and heritability size were analyzed and calculated. [Result]The results showed that NUEg has obvious heterosis; combining ability variance analysis indicated that NUEg was mainly controlled by additive,dominant and cytoplasmic effects; genetic variance analysis showed that additive effects and dominance effects were all significant in low nitrogen fertilizer and dominance effects were significant in high nitrogen fertilizer. [Conclusion]NUEg of B.napus has obvious heterosis.展开更多
[Objective] This study aimed at investigating the effects of consumption of potassium fertilizer on production and biological characteristics of rape and utilizing efficiency of potassium fertilizer.[Method] Taking 0 ...[Objective] This study aimed at investigating the effects of consumption of potassium fertilizer on production and biological characteristics of rape and utilizing efficiency of potassium fertilizer.[Method] Taking 0 kg/hm2 as control,nine consumptions of potassium fertilizer were designed for the experiment using single factor randomized block design with three replications and field experiment in nine rape-producing areas with different ecological types in Yunnan Province.[Result] Appropriately applying potassium fertilizer in Yunnan Province could improve the rapeseed production,the rape production could achieve 3 983-4 151 kg when applied 150-180 kg/hm2 of K2O,which had increased by 4.7-9.1% compared with the control and attained the peak in K165 treatment.When applied 1 kg of K2O,the rapeseed production could enhance 559 kg,the net profit could reach 1 229 yuan/hm2 and the partial productivity of potassium fertilizer could attain 31.32 kg/kg K2O and 3.7 kg/kg K2O,respectively.Applying potassium fertilizer could promote the growth of rape and increase rapeseed production.[Conclusion] The recommended optimal consumptions of potassium fertilizer with high production and high efficiency for rape in Yunnan Province were ranged between 150 and 180 kg K2O/hm2.However,comprehensively considering production and efficiency factors,the consumption of potassium fertilizer in Yunnan Province was around 73.9 kg/hm2,which should be appropriately increased to around 100.0 kg/hm2 in Longchuan,Yulong,Linxiang and other producing areas with similar conditions.展开更多
The research explored productive efficiencies of main crops in the decade in Hunan by nonparametric DEA method and the results showed that net output value and net-profit rate of potato and sweet potato were extremely...The research explored productive efficiencies of main crops in the decade in Hunan by nonparametric DEA method and the results showed that net output value and net-profit rate of potato and sweet potato were extremely higher than those of rice and maize, and comprehensive efficiencies from high to low were potato, rice, sweet potato and maize. It is recommended that scales of rice, maize, and sweet potato should be reduced to certain extent and the scale of potato pro- duction extended. Besides, direct fee and labor cost should be lowered as much as possible to improve net-profit rate, accelerate crop S&T development and improve grain productive efficiency.展开更多
To analyze and estimate the environmental efficiency of China’s vegetable production. Methods The stochastic translog frontier model was used to estimate the technical efficiency of vegetable production. Based on...To analyze and estimate the environmental efficiency of China’s vegetable production. Methods The stochastic translog frontier model was used to estimate the technical efficiency of vegetable production. Based on the estimated frontier and technical inefficiency levels, we used the method developed by Reinhard, et al.[1] to estimate the environmental efficiency. Pesticide and chemical fertilizer inputs were treated as environmentally detrimental inputs. Results From estimated results, the mean environmental efficiency for pesticide input was 69.7%, indicating a great potential for reducing pesticide use in China’s vegetable production. In addition, substitution and output elasticities for vegetable farms were estimated to provide farmers with helpful information on how to reallocate input resources and improve efficiency. Conclusion There exists a great potential for reducing pesticide use in China’s vegetable production.展开更多
This paper aims to establish an index system for evaluation of agricultural resources use efficiency(ARUE) in grain production and discuss the causes of low efficiency and high consumption of agricultural resources in...This paper aims to establish an index system for evaluation of agricultural resources use efficiency(ARUE) in grain production and discuss the causes of low efficiency and high consumption of agricultural resources in Changshu of Jiangsu Province,Taihe of Jiangxi Province and Ansai of Shaanxi Province in China by analyzing the data about meteorology,soil,water consumption and grain production. Agro-ecological Zone(AEZ) method was adopted to calculate the potential productivity,and synthetically multivariate equation was used to evaluate the ARUE of study areas. This paper can be concluded as:1) the agricultural resources in grain production can be classified into five categories,i.e.,climatic resources,water resources,land resources,biological resources and assistant resources,and 15 indexes were selected to evaluate their use efficiency in grain production;2) the values of ARUE in grain production are 0.5868,0.6368 and 0.5390 respectively in Changshu,Taihe and Ansai;and 3) Changshu ranks the highest among the three study areas in terms of the use efficiency of climatic resources and biological resources(evaluation values are 0.0277 and 0.1530) ,but Taihe tops the three in terms of the use efficiency of water resources,land resources and assistant resources(evaluation values are 0.0502,0.2945 and 0.1379 respectively) . However,the ARUE remains always low in Ansai for all the resources. The inefficiencies are caused by poor grain revenue in Changshu,deficient agriculture investments in Taihe and unfavorable natural conditions in Ansai.展开更多
The above-ground net primary production(ANPP) and the precipitation-use efficiency(PUE) regulate the carbon and water cycles in grassland ecosystems, but the relationships among the ANPP, PUE and precipitation are sti...The above-ground net primary production(ANPP) and the precipitation-use efficiency(PUE) regulate the carbon and water cycles in grassland ecosystems, but the relationships among the ANPP, PUE and precipitation are still controversial. We selected 717 grassland sites with ANPP and mean annual precipitation(MAP) data from 40 publications to characterize the relationships ANPP–MAP and PUE–MAP across different grassland types. The MAP and ANPP showed large variations across all grassland types, ranging from 69 to 2335 mm and 4.3 to 1706 g m^(-2), respectively. The global maximum PUE ranged from 0.19 to 1.49 g m^(-2) mm^(-1) with a unimodal pattern. Analysis using the sigmoid function explained the ANPP–MAP relationship best at the global scale. The gradient of the ANPP–MAP graph was small for arid and semi-arid sites(MAP <400 mm). This study improves our understanding of the relationship between ANPP and MAP across dry grassland ecosystems. It provides new perspectives on the prediction and modeling of variations in the ANPP for different grassland types along precipitation gradients.展开更多
Energy efficiency data from ethylene production equipment are of high dimension, dynamic and time sequential, so their evaluation is affected by many factors. Abnormal data from ethylene production are eliminated thro...Energy efficiency data from ethylene production equipment are of high dimension, dynamic and time sequential, so their evaluation is affected by many factors. Abnormal data from ethylene production are eliminated through consistency test, making the data consumption uniform to improve the comparability of data. Due to the limit of input and output data of decision making unit in data envelopment analysis(DEA), the energy efficiency data from the same technology in a certain year are disposed monthly using DEA. The DEA data of energy efficiency from the same technology are weighted and fused using analytic hierarchy process. The energy efficiency data from different technologies are evaluated by their relative effectiveness to find the direction of energy saving and consumption reduction.展开更多
Using DEA- Malmquist index method,we perform an empirical analysis of Japonica rice production input- output panel data in 12China's major Japonica rice producing areas during 2001- 2012,calculate the total factor...Using DEA- Malmquist index method,we perform an empirical analysis of Japonica rice production input- output panel data in 12China's major Japonica rice producing areas during 2001- 2012,calculate the total factor input- output efficiency of China's major Japonica rice producing areas,and analyze TFP change and convergence of Japonica rice. It is found that from 2001 to 2012,the average growth rate of total factor productivity( TFP) was- 2. 3% and the technological progress was- 2. 2%,and the decline of technical progress was the main cause of the decrease of TFP. Moreover,significant differences exist between the TFP of these provinces,and the TFP of Heilongjiang and Jiangsu is higher than that of other provinces. Further convergence test indicates that TFP of the main producing areas shows σ convergence trend.展开更多
Based on micro survey data of 344 rapeseed farmers in 19 rapeseed counties of Hubei Province,with the aid of stochastic frontier production function model and efficiency loss model,this paper analyzed basic production...Based on micro survey data of 344 rapeseed farmers in 19 rapeseed counties of Hubei Province,with the aid of stochastic frontier production function model and efficiency loss model,this paper analyzed basic production situations,demographic characteristics of rapeseed farmers,technical efficiency loss,and main influencing factors. In Hubei Province,there are mainly following problems in rapeseed production: serious aging of rapeseed farmers; relatively scarce labors; the middle-aged and old farmers have higher technical efficiency level; with increase in farmer age,their technical efficiency firstly declines and then rises. In view of these situations,it came up with recommendations including raising educational level of rapeseed farmers to realize large scale economy and effectively reduce technical efficiency loss,and local government,specialized associations and agricultural machinery extension departments should provide proper technical guidance according to demands of farmers to reduce technical efficiency loss.展开更多
Energy efficiency evaluation plays an important role in energy efficiency improvement of the ethylene production. It is observed from the actual production data that the ethylene production energy efficiency often var...Energy efficiency evaluation plays an important role in energy efficiency improvement of the ethylene production. It is observed from the actual production data that the ethylene production energy efficiency often varies with the complex production working conditions. In the favored methods for energy efficiency evaluation,DEA models may show poor resolution when directly used to evaluate the efficiency values. Therefore, a new energy efficiency evaluation method for ethylene production is proposed based on DEA integrated factor analysis with respect to operation classification. Three key factors, including raw material composition, cracking depth and load rate, are taken into account in determining the production working conditions by means of k-means algorithm. Based on the multi-working conditions mode the energy efficiency evaluation of the ethylene production is made by using DEA model, where the most related energy data are screened by factor analysis.Furthermore, the supporting decision of energy efficiency improvement is provided to the operators. The accuracy and effectiveness of the proposed method are illustrated by applying in a practical ethylene production,which gives more effective energy efficiency evaluation in the complicated working conditions of ethylene production with declined dimension of input indicators.展开更多
Pig production efficiency and its regional differences in China have strategic importance to the transformation of pig production mode and optimization of pig production layout in China. In this paper,Malmquist-DEA mo...Pig production efficiency and its regional differences in China have strategic importance to the transformation of pig production mode and optimization of pig production layout in China. In this paper,Malmquist-DEA model is adopted to analyze the statistical data; TFP and its decomposition indicators of different pig breeding scale among the top ten pig producing provinces are calculated; both horizontal and longitudinal comparisons are made. Results show that among different pig breeding scales,free-range breeding scale is dominant in Hunan,small breeding scale is dominant in Sichuan,medium breeding scale is dominant in Sichuan and Hunan,and large breeding scale is dominant in Sichuan,Shandong and Jiangsu; among the provinces,pig production efficiency varies with breeding scale,and small-scale pig breeding in Sichuan,Guangdong and Hebei,free-range and medium-scale pig breeding in Hunan,medium-scale pig breeding in Henan and Yunnan,largescale pig breeding in the rest of the provinces,have significant efficiency advantage.展开更多
On the basis of summarizing some literatures regarding research of agricultural production efficiency by using DEA at home,we conduct empirical analysis on agricultural production efficiency in 18 cities or counties o...On the basis of summarizing some literatures regarding research of agricultural production efficiency by using DEA at home,we conduct empirical analysis on agricultural production efficiency in 18 cities or counties of Hainan Province in the year 2002,2005 and 2008 by using DEA model.The results show that in 2005 Hainan Province suffered from unusual drought and windstorm,which made the effective value of agricultural production in all cities or counties relatively low;the regions with DEA effectiveness of agricultural production in the year 2002,2005 and 2008 were Qionghai City,Tunchang County,Lingao County,Danzhou City,Qiongzhong County and Baisha County.Haikou City,Wuzhishan City and Baoting County in the year 2002,Lingshui County in the year 2005,and Sanya City and Dongfang County in the year 2008 were also regions with DEA effectiveness,indicating that the input-output of these regions in the corresponding years is in optimal state.Finally,we conduct projection analysis on six cities and counties with non-DEA effectiveness in the year 2008 in Hainan Province,and based on this,find out the approach of improving agricultural production efficiency in these regions.展开更多
Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain sub...Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain subsidy policy,and made an empirical analysis on the relationship between the direct grain subsidy policy and the changes in the rice production performance. The results showed that the effect of the direct grain subsidy policy on promoting the rice production performance is declining year by year,largely because drop of scale efficiency. Besides,there are problems of serious redundancy in agricultural subsidy,unreasonable resource allocation,leading to low performance and resource waste of rice production.展开更多
It is aimed to investigate the efficiency of nitrogen gas cooling which is used in aluminium extrusion mold in this study. The exit temperature of extrusion profile increases depending on heat generated by friction an...It is aimed to investigate the efficiency of nitrogen gas cooling which is used in aluminium extrusion mold in this study. The exit temperature of extrusion profile increases depending on heat generated by friction and forming. This situation can cause to surface defects such as hot cracks and grain thickening after extrusion process. Cooling of the mold has a critical role in terms of dissipating heat close to the forming zone. Local internal cooling experiments were performed in the hot aluminium extrusion mold within the scope of this study. It has been obtained that exit temperature of the aluminium extrusion profile can be significantly reduced in experimental results. Also it was found that the reduction of press time (s) and increase of press speed (mm/s). This paper focuses the effect of nitrogen gas cooling on extrusion mold for process efficiency. The extrusion parameters were performed for comparative analysis. Its obtained that process ensures efficiency.展开更多
Agricultural production efficiency in Taiwan of China in 2015 is studied by using three-stage DEA model. The results show that total output value of agriculture,forestry,animal husbandry and fishery is taken as output...Agricultural production efficiency in Taiwan of China in 2015 is studied by using three-stage DEA model. The results show that total output value of agriculture,forestry,animal husbandry and fishery is taken as output index,while employees of agriculture,forestry,animal husbandry and fishery,number of tractors,investment in dry land and paddy field are taken as input indexes,which meets " isotropic" condition assumption of model application. Natural disaster,number of workers in agricultural production and marketing class,expenditure on farmland water conservancy are not favorable for the promotion of agricultural production efficiency,while multiple cropping index is favorable for promoting agricultural production efficiency. Three-stage DEA model effectively eliminates the influences of environmental and random factors on agricultural production efficiency. After environmental and random factors are eliminated,comprehensive technical efficiency in Taiwan of China declines because of the decline of pure technical efficiency. Each county and city of Taiwan could be divided into different types according to pure technical efficiency and scale efficiency,and it can have some emphasis in improving agricultural production efficiency according to their own efficiency characteristics.展开更多
Literatures about agricultural production efficiency are reviewed.Concept of DEA Method,as well as the definition methods of effective DEA and scale efficiency increase are introduced.According to the relevant statist...Literatures about agricultural production efficiency are reviewed.Concept of DEA Method,as well as the definition methods of effective DEA and scale efficiency increase are introduced.According to the relevant statistical data in the years 1997-2007 in Chongqing Municipality,efficiency of agricultural economy is calculated from the year 1997 to 2007 by DEA method and the scale efficiency is also analyzed by taking the total output of agriculture,forestry,animal husbandry and fishery industry as the output index.And the input index includes total workforce in agriculture,forestry,animal husbandry and fishery,the total sown area of crops,the total power of agricultural machinery,chemical fertilizer application,the draft animal,and the effective irrigation area.Result shows that Chongqing City became a municipality directly under the central government;its agricultural production efficiency is still low.And the sustainable development capacity of agricultural is weak in Chongqing,and the agricultural resources are not fully used.Based on this,related suggestions are put forward to improve the agricultural production efficiency of Chongqing,such as implementing an appropriate management scale of land,improving the organization degree of peasant households and the rate of industrialization management,enhancing the quality of the rural labor force,strengthening the agricultural science and technology input and extension,perfecting the construction of rural infrastructure,and improving the rate of resource utilization.展开更多
Based on DEA-Malmquist method,this paper calculated the integrated technology efficiency of grain production and total factor productivity and analyzed factors influencing the grain production technology efficiency us...Based on DEA-Malmquist method,this paper calculated the integrated technology efficiency of grain production and total factor productivity and analyzed factors influencing the grain production technology efficiency using working documents of panel structure. Research results indicate that grain production integrated technology efficiency of China is relatively low,technology utilization level is low,and it remains at the stage of decreasing returns to scale,and the pure technology efficiency still has space to increase. Total factor productivity is declining and the total factor productivity of many provinces is relatively low. Since the total factor productivity of eastern areas is higher than central and western areas,it is required to strengthen technological support for grain production. The implementation of urbanization is helpful for promoting increase of grain production technology efficiency in central and eastern areas,but it will exert negative influence on western areas.展开更多
Proton conducting ceramic cells(PCCs)are an attractive emerging technology operating in the intermediate temperature range of 500 to 700℃.In this work,we evaluate the production of hydrogen at intermediate temperatur...Proton conducting ceramic cells(PCCs)are an attractive emerging technology operating in the intermediate temperature range of 500 to 700℃.In this work,we evaluate the production of hydrogen at intermediate temperatures by proton conducting ceramic cell electrolysis(PCCEL).We demonstrate a highperformance steam electrolysis owing to a composite positrode based on BaGd_(0.8)La_(0.2)Co_(2)O_(6-δ)(BGLC1082)and BaZr0.5Ce0.4Y0.1O3-δ(BZCY541).The high reliability of PCCEL is demonstrated for 1680 h at a current density as high as-0.8 A cm^(-2)close to the thermoneutral cell voltage at 600℃.The electrolysis cell showed a specific energy consumption ranging from 54 to 66 kW h kg^(-1)that is comparable to state-of-the-art low temperature electrolysis technologies,while showing hydrogen production rates systematically higher than commercial solid oxide ceramic cells(SOCs).Compared to SOCs,the results verified the higher performances of PCCs at the relevant operating temperatures,due to the lower activation energy for proton transfer comparing with oxygen ion conduction.However,because of the p-type electronic conduction in protonic ceramics,the energy conversion rate of PCCs is relatively lower in steam electrolysis.The faradaic efficiency of the PCC in electrolysis mode can be increased at lower operating temperatures and in endothermic conditions,making PCCEL a technology of choice to valorize high temperature waste heat from industrial processes into hydrogen.To increase the faradaic efficiency by optimizing the materials,the cell design,or the operating strategy is a key challenge to address for future developments of PCCEL in order to achieve even more superior techno-economic merits.展开更多
China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-p...China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-producing areas has become the fundamental way to strengthen the grain production capacity and improve the national food security capability,and to improve the efficiency of grain production in major grain-producing areas requires empirical support.This paper used the Super SBM model and the Malmquist index to measure the grain production efficiency of the main grain-producing areas from 2001 to 2020 from both static and dynamic perspectives,and compared the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas.The results showed that from 2001 to 2020,the grain production in the main grain-producing areas was in a relatively ineffective state,and the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas were obvious.The order of grain production efficiency in different soil types was black soil region>red-yellow soil region>paddy soil region>fluvo-aquic soil region,and the order of grain production efficiency of the provinces(autonomous regions)in the main grain-producing areas was Jilin>Heilongjiang>Inner Mongolia>Jiangxi>Hunan>Sichuan>Hubei>Jiangsu>Liaoning>Henan>Anhui>Shandong>Hebei.From 2001 to 2020,the total factor productivity of grain in the main grain-producing areas increased,but due to the trade-off between the technological progress and the growth of technical efficiency,the increase in the total factor productivity of grain in the main grain-producing areas was small,and the growth mainly came from the increase of input factors in this period.The total factor productivity of grain in Hebei,Heilongjiang,Liaoning,Jilin,Inner Mongolia,Shandong,Jiangsu,Henan and Anhui increased,but the increase was small,while the total factor productivity of grain in Jiangxi,Sichuan,Hunan and Hubei provinces declined.展开更多
The increased production efficiency of heat treatable A1 alloys, as the result of applied electromagnetic field during continuous casting process was investigated. The applied frequency of the electromagnetic field (...The increased production efficiency of heat treatable A1 alloys, as the result of applied electromagnetic field during continuous casting process was investigated. The applied frequency of the electromagnetic field (EMF) during the AI alloys continuous casting was changing from 30 Hz to 50 Hz, while some castings were obtained without the EMF influence. The mechanical characterization of continuous casted AI alloys EN AW 2007 and En AW 2024 was done on testing machine Zwick/Roell Z 100. The microstructure of as-cast samples was examined, as well. When the frequency decreases (from 50 Hz to 30 Hz), the grain size decreases as well, what is noticeable through the finer microstructure and its uniformity throughout the cross-section. These results have shown that low frequency electromagnetic field significantly influenced the microstructure and therefore the mechanical properties of as cast ingots. Thus, through improved castings quality, operation time and energy savings, the production efficiency was increased.展开更多
基金Supported by Agricultural Science &Technology Project of Jiangsu Province(BE2008369)~~
文摘[Objective]The aim was to study heterosis of N use efficiency for grain production (NUEg) of Brassica napus L. and provide theoretical basis for breeding N-efficient cultivars. [Method]Dry matter production and N content of six B.napus parents (Zheshuang 3,Yangyou 7,ZJ1,Shilijia,Ningyou 14 and Huyou 16) and their F1 combinations from 6 × 6 complete diallel cross in maturity stage under two N levels were measured; heterosis of NUEg,combining ability and heritability size were analyzed and calculated. [Result]The results showed that NUEg has obvious heterosis; combining ability variance analysis indicated that NUEg was mainly controlled by additive,dominant and cytoplasmic effects; genetic variance analysis showed that additive effects and dominance effects were all significant in low nitrogen fertilizer and dominance effects were significant in high nitrogen fertilizer. [Conclusion]NUEg of B.napus has obvious heterosis.
基金Supported by the National Science and Technology Support Program(2009BADA8B01)Kunming Comprehensive Experimental Station,National Modern Agricultural Industrial Technology System of Rape(NYCYTX-00564)Yunnan Modern Agricultural Industrial Technology System Construction of Rape~~
文摘[Objective] This study aimed at investigating the effects of consumption of potassium fertilizer on production and biological characteristics of rape and utilizing efficiency of potassium fertilizer.[Method] Taking 0 kg/hm2 as control,nine consumptions of potassium fertilizer were designed for the experiment using single factor randomized block design with three replications and field experiment in nine rape-producing areas with different ecological types in Yunnan Province.[Result] Appropriately applying potassium fertilizer in Yunnan Province could improve the rapeseed production,the rape production could achieve 3 983-4 151 kg when applied 150-180 kg/hm2 of K2O,which had increased by 4.7-9.1% compared with the control and attained the peak in K165 treatment.When applied 1 kg of K2O,the rapeseed production could enhance 559 kg,the net profit could reach 1 229 yuan/hm2 and the partial productivity of potassium fertilizer could attain 31.32 kg/kg K2O and 3.7 kg/kg K2O,respectively.Applying potassium fertilizer could promote the growth of rape and increase rapeseed production.[Conclusion] The recommended optimal consumptions of potassium fertilizer with high production and high efficiency for rape in Yunnan Province were ranged between 150 and 180 kg K2O/hm2.However,comprehensively considering production and efficiency factors,the consumption of potassium fertilizer in Yunnan Province was around 73.9 kg/hm2,which should be appropriately increased to around 100.0 kg/hm2 in Longchuan,Yulong,Linxiang and other producing areas with similar conditions.
基金Supported by Hunan Key Financial Project([2014]74)~~
文摘The research explored productive efficiencies of main crops in the decade in Hunan by nonparametric DEA method and the results showed that net output value and net-profit rate of potato and sweet potato were extremely higher than those of rice and maize, and comprehensive efficiencies from high to low were potato, rice, sweet potato and maize. It is recommended that scales of rice, maize, and sweet potato should be reduced to certain extent and the scale of potato pro- duction extended. Besides, direct fee and labor cost should be lowered as much as possible to improve net-profit rate, accelerate crop S&T development and improve grain productive efficiency.
文摘To analyze and estimate the environmental efficiency of China’s vegetable production. Methods The stochastic translog frontier model was used to estimate the technical efficiency of vegetable production. Based on the estimated frontier and technical inefficiency levels, we used the method developed by Reinhard, et al.[1] to estimate the environmental efficiency. Pesticide and chemical fertilizer inputs were treated as environmentally detrimental inputs. Results From estimated results, the mean environmental efficiency for pesticide input was 69.7%, indicating a great potential for reducing pesticide use in China’s vegetable production. In addition, substitution and output elasticities for vegetable farms were estimated to provide farmers with helpful information on how to reallocate input resources and improve efficiency. Conclusion There exists a great potential for reducing pesticide use in China’s vegetable production.
基金Under the auspices of National Natural Science Foundation of China (No. 70673097)
文摘This paper aims to establish an index system for evaluation of agricultural resources use efficiency(ARUE) in grain production and discuss the causes of low efficiency and high consumption of agricultural resources in Changshu of Jiangsu Province,Taihe of Jiangxi Province and Ansai of Shaanxi Province in China by analyzing the data about meteorology,soil,water consumption and grain production. Agro-ecological Zone(AEZ) method was adopted to calculate the potential productivity,and synthetically multivariate equation was used to evaluate the ARUE of study areas. This paper can be concluded as:1) the agricultural resources in grain production can be classified into five categories,i.e.,climatic resources,water resources,land resources,biological resources and assistant resources,and 15 indexes were selected to evaluate their use efficiency in grain production;2) the values of ARUE in grain production are 0.5868,0.6368 and 0.5390 respectively in Changshu,Taihe and Ansai;and 3) Changshu ranks the highest among the three study areas in terms of the use efficiency of climatic resources and biological resources(evaluation values are 0.0277 and 0.1530) ,but Taihe tops the three in terms of the use efficiency of water resources,land resources and assistant resources(evaluation values are 0.0502,0.2945 and 0.1379 respectively) . However,the ARUE remains always low in Ansai for all the resources. The inefficiencies are caused by poor grain revenue in Changshu,deficient agriculture investments in Taihe and unfavorable natural conditions in Ansai.
基金jointly funded by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20020401)the Young Foundation of Institute of Mountain Hazard and Environment(SDS-QN-1702)National Natural Science Foundation of China(Grant No.41571205)
文摘The above-ground net primary production(ANPP) and the precipitation-use efficiency(PUE) regulate the carbon and water cycles in grassland ecosystems, but the relationships among the ANPP, PUE and precipitation are still controversial. We selected 717 grassland sites with ANPP and mean annual precipitation(MAP) data from 40 publications to characterize the relationships ANPP–MAP and PUE–MAP across different grassland types. The MAP and ANPP showed large variations across all grassland types, ranging from 69 to 2335 mm and 4.3 to 1706 g m^(-2), respectively. The global maximum PUE ranged from 0.19 to 1.49 g m^(-2) mm^(-1) with a unimodal pattern. Analysis using the sigmoid function explained the ANPP–MAP relationship best at the global scale. The gradient of the ANPP–MAP graph was small for arid and semi-arid sites(MAP <400 mm). This study improves our understanding of the relationship between ANPP and MAP across dry grassland ecosystems. It provides new perspectives on the prediction and modeling of variations in the ANPP for different grassland types along precipitation gradients.
基金Supported by the National Natural Science Foundation of China(61374166)the Doctoral Fund of Ministry of Education of China(20120010110010)the Fundamental Research Funds for the Central Universities(YS1404)
文摘Energy efficiency data from ethylene production equipment are of high dimension, dynamic and time sequential, so their evaluation is affected by many factors. Abnormal data from ethylene production are eliminated through consistency test, making the data consumption uniform to improve the comparability of data. Due to the limit of input and output data of decision making unit in data envelopment analysis(DEA), the energy efficiency data from the same technology in a certain year are disposed monthly using DEA. The DEA data of energy efficiency from the same technology are weighted and fused using analytic hierarchy process. The energy efficiency data from different technologies are evaluated by their relative effectiveness to find the direction of energy saving and consumption reduction.
基金Supported by Scientific Research Foundation for Chinese Students and Scholars Studying Abroad by the Ministry of Human Resources and Social Security(2014240)Fujian Natural Science Fund Project(2015J01284)+1 种基金Fujian Science and Technology Planning Project-Special Research Fund for Provincial Public Welfare Research Institutes(2014R1016-3)Scientific Research Foundation for Doctor in Fujian Academy of Agricultural Sciences(2013DBS-1)
文摘Using DEA- Malmquist index method,we perform an empirical analysis of Japonica rice production input- output panel data in 12China's major Japonica rice producing areas during 2001- 2012,calculate the total factor input- output efficiency of China's major Japonica rice producing areas,and analyze TFP change and convergence of Japonica rice. It is found that from 2001 to 2012,the average growth rate of total factor productivity( TFP) was- 2. 3% and the technological progress was- 2. 2%,and the decline of technical progress was the main cause of the decrease of TFP. Moreover,significant differences exist between the TFP of these provinces,and the TFP of Heilongjiang and Jiangsu is higher than that of other provinces. Further convergence test indicates that TFP of the main producing areas shows σ convergence trend.
文摘Based on micro survey data of 344 rapeseed farmers in 19 rapeseed counties of Hubei Province,with the aid of stochastic frontier production function model and efficiency loss model,this paper analyzed basic production situations,demographic characteristics of rapeseed farmers,technical efficiency loss,and main influencing factors. In Hubei Province,there are mainly following problems in rapeseed production: serious aging of rapeseed farmers; relatively scarce labors; the middle-aged and old farmers have higher technical efficiency level; with increase in farmer age,their technical efficiency firstly declines and then rises. In view of these situations,it came up with recommendations including raising educational level of rapeseed farmers to realize large scale economy and effectively reduce technical efficiency loss,and local government,specialized associations and agricultural machinery extension departments should provide proper technical guidance according to demands of farmers to reduce technical efficiency loss.
基金Supported by the High-tech Research and Development Program of China(2014AA041802)Fundamental Research Funds for the Central Universities(DUT15RC(3)007)
文摘Energy efficiency evaluation plays an important role in energy efficiency improvement of the ethylene production. It is observed from the actual production data that the ethylene production energy efficiency often varies with the complex production working conditions. In the favored methods for energy efficiency evaluation,DEA models may show poor resolution when directly used to evaluate the efficiency values. Therefore, a new energy efficiency evaluation method for ethylene production is proposed based on DEA integrated factor analysis with respect to operation classification. Three key factors, including raw material composition, cracking depth and load rate, are taken into account in determining the production working conditions by means of k-means algorithm. Based on the multi-working conditions mode the energy efficiency evaluation of the ethylene production is made by using DEA model, where the most related energy data are screened by factor analysis.Furthermore, the supporting decision of energy efficiency improvement is provided to the operators. The accuracy and effectiveness of the proposed method are illustrated by applying in a practical ethylene production,which gives more effective energy efficiency evaluation in the complicated working conditions of ethylene production with declined dimension of input indicators.
基金Supported by Pig Innovation Team Project of Shandong Provincial Modern Agricultural Technology System(SDAIT-06-022-10)
文摘Pig production efficiency and its regional differences in China have strategic importance to the transformation of pig production mode and optimization of pig production layout in China. In this paper,Malmquist-DEA model is adopted to analyze the statistical data; TFP and its decomposition indicators of different pig breeding scale among the top ten pig producing provinces are calculated; both horizontal and longitudinal comparisons are made. Results show that among different pig breeding scales,free-range breeding scale is dominant in Hunan,small breeding scale is dominant in Sichuan,medium breeding scale is dominant in Sichuan and Hunan,and large breeding scale is dominant in Sichuan,Shandong and Jiangsu; among the provinces,pig production efficiency varies with breeding scale,and small-scale pig breeding in Sichuan,Guangdong and Hebei,free-range and medium-scale pig breeding in Hunan,medium-scale pig breeding in Henan and Yunnan,largescale pig breeding in the rest of the provinces,have significant efficiency advantage.
文摘On the basis of summarizing some literatures regarding research of agricultural production efficiency by using DEA at home,we conduct empirical analysis on agricultural production efficiency in 18 cities or counties of Hainan Province in the year 2002,2005 and 2008 by using DEA model.The results show that in 2005 Hainan Province suffered from unusual drought and windstorm,which made the effective value of agricultural production in all cities or counties relatively low;the regions with DEA effectiveness of agricultural production in the year 2002,2005 and 2008 were Qionghai City,Tunchang County,Lingao County,Danzhou City,Qiongzhong County and Baisha County.Haikou City,Wuzhishan City and Baoting County in the year 2002,Lingshui County in the year 2005,and Sanya City and Dongfang County in the year 2008 were also regions with DEA effectiveness,indicating that the input-output of these regions in the corresponding years is in optimal state.Finally,we conduct projection analysis on six cities and counties with non-DEA effectiveness in the year 2008 in Hainan Province,and based on this,find out the approach of improving agricultural production efficiency in these regions.
文摘Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain subsidy policy,and made an empirical analysis on the relationship between the direct grain subsidy policy and the changes in the rice production performance. The results showed that the effect of the direct grain subsidy policy on promoting the rice production performance is declining year by year,largely because drop of scale efficiency. Besides,there are problems of serious redundancy in agricultural subsidy,unreasonable resource allocation,leading to low performance and resource waste of rice production.
文摘It is aimed to investigate the efficiency of nitrogen gas cooling which is used in aluminium extrusion mold in this study. The exit temperature of extrusion profile increases depending on heat generated by friction and forming. This situation can cause to surface defects such as hot cracks and grain thickening after extrusion process. Cooling of the mold has a critical role in terms of dissipating heat close to the forming zone. Local internal cooling experiments were performed in the hot aluminium extrusion mold within the scope of this study. It has been obtained that exit temperature of the aluminium extrusion profile can be significantly reduced in experimental results. Also it was found that the reduction of press time (s) and increase of press speed (mm/s). This paper focuses the effect of nitrogen gas cooling on extrusion mold for process efficiency. The extrusion parameters were performed for comparative analysis. Its obtained that process ensures efficiency.
基金Supported by Special Fund of National Modern Agricultural (Citrus) Industry Technology System (MATS) of Ministry of Agriculture(CARS-26-07B)
文摘Agricultural production efficiency in Taiwan of China in 2015 is studied by using three-stage DEA model. The results show that total output value of agriculture,forestry,animal husbandry and fishery is taken as output index,while employees of agriculture,forestry,animal husbandry and fishery,number of tractors,investment in dry land and paddy field are taken as input indexes,which meets " isotropic" condition assumption of model application. Natural disaster,number of workers in agricultural production and marketing class,expenditure on farmland water conservancy are not favorable for the promotion of agricultural production efficiency,while multiple cropping index is favorable for promoting agricultural production efficiency. Three-stage DEA model effectively eliminates the influences of environmental and random factors on agricultural production efficiency. After environmental and random factors are eliminated,comprehensive technical efficiency in Taiwan of China declines because of the decline of pure technical efficiency. Each county and city of Taiwan could be divided into different types according to pure technical efficiency and scale efficiency,and it can have some emphasis in improving agricultural production efficiency according to their own efficiency characteristics.
文摘Literatures about agricultural production efficiency are reviewed.Concept of DEA Method,as well as the definition methods of effective DEA and scale efficiency increase are introduced.According to the relevant statistical data in the years 1997-2007 in Chongqing Municipality,efficiency of agricultural economy is calculated from the year 1997 to 2007 by DEA method and the scale efficiency is also analyzed by taking the total output of agriculture,forestry,animal husbandry and fishery industry as the output index.And the input index includes total workforce in agriculture,forestry,animal husbandry and fishery,the total sown area of crops,the total power of agricultural machinery,chemical fertilizer application,the draft animal,and the effective irrigation area.Result shows that Chongqing City became a municipality directly under the central government;its agricultural production efficiency is still low.And the sustainable development capacity of agricultural is weak in Chongqing,and the agricultural resources are not fully used.Based on this,related suggestions are put forward to improve the agricultural production efficiency of Chongqing,such as implementing an appropriate management scale of land,improving the organization degree of peasant households and the rate of industrialization management,enhancing the quality of the rural labor force,strengthening the agricultural science and technology input and extension,perfecting the construction of rural infrastructure,and improving the rate of resource utilization.
基金Supported by Project of National Natural Science Foundation(71373215)Key Project of Fundamental Research Funds for Southwest University(SWU1309003)Fundamental Research Funds for the Central Universities in 2015(SWU1509317)
文摘Based on DEA-Malmquist method,this paper calculated the integrated technology efficiency of grain production and total factor productivity and analyzed factors influencing the grain production technology efficiency using working documents of panel structure. Research results indicate that grain production integrated technology efficiency of China is relatively low,technology utilization level is low,and it remains at the stage of decreasing returns to scale,and the pure technology efficiency still has space to increase. Total factor productivity is declining and the total factor productivity of many provinces is relatively low. Since the total factor productivity of eastern areas is higher than central and western areas,it is required to strengthen technological support for grain production. The implementation of urbanization is helpful for promoting increase of grain production technology efficiency in central and eastern areas,but it will exert negative influence on western areas.
基金The China Scholarship Council is acknowledged for the doctoral scholarship of Haoyu Zheng(201806160173)The German Federal Ministry for Education and Research is acknowledged for funding via the Project ARCADE(03SF0580A)。
文摘Proton conducting ceramic cells(PCCs)are an attractive emerging technology operating in the intermediate temperature range of 500 to 700℃.In this work,we evaluate the production of hydrogen at intermediate temperatures by proton conducting ceramic cell electrolysis(PCCEL).We demonstrate a highperformance steam electrolysis owing to a composite positrode based on BaGd_(0.8)La_(0.2)Co_(2)O_(6-δ)(BGLC1082)and BaZr0.5Ce0.4Y0.1O3-δ(BZCY541).The high reliability of PCCEL is demonstrated for 1680 h at a current density as high as-0.8 A cm^(-2)close to the thermoneutral cell voltage at 600℃.The electrolysis cell showed a specific energy consumption ranging from 54 to 66 kW h kg^(-1)that is comparable to state-of-the-art low temperature electrolysis technologies,while showing hydrogen production rates systematically higher than commercial solid oxide ceramic cells(SOCs).Compared to SOCs,the results verified the higher performances of PCCs at the relevant operating temperatures,due to the lower activation energy for proton transfer comparing with oxygen ion conduction.However,because of the p-type electronic conduction in protonic ceramics,the energy conversion rate of PCCs is relatively lower in steam electrolysis.The faradaic efficiency of the PCC in electrolysis mode can be increased at lower operating temperatures and in endothermic conditions,making PCCEL a technology of choice to valorize high temperature waste heat from industrial processes into hydrogen.To increase the faradaic efficiency by optimizing the materials,the cell design,or the operating strategy is a key challenge to address for future developments of PCCEL in order to achieve even more superior techno-economic merits.
基金Supported by Science of China University Journals(CUJS2021-027)China Agricultural Journals Website 2021(CAJW2021-033)。
文摘China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-producing areas has become the fundamental way to strengthen the grain production capacity and improve the national food security capability,and to improve the efficiency of grain production in major grain-producing areas requires empirical support.This paper used the Super SBM model and the Malmquist index to measure the grain production efficiency of the main grain-producing areas from 2001 to 2020 from both static and dynamic perspectives,and compared the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas.The results showed that from 2001 to 2020,the grain production in the main grain-producing areas was in a relatively ineffective state,and the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas were obvious.The order of grain production efficiency in different soil types was black soil region>red-yellow soil region>paddy soil region>fluvo-aquic soil region,and the order of grain production efficiency of the provinces(autonomous regions)in the main grain-producing areas was Jilin>Heilongjiang>Inner Mongolia>Jiangxi>Hunan>Sichuan>Hubei>Jiangsu>Liaoning>Henan>Anhui>Shandong>Hebei.From 2001 to 2020,the total factor productivity of grain in the main grain-producing areas increased,but due to the trade-off between the technological progress and the growth of technical efficiency,the increase in the total factor productivity of grain in the main grain-producing areas was small,and the growth mainly came from the increase of input factors in this period.The total factor productivity of grain in Hebei,Heilongjiang,Liaoning,Jilin,Inner Mongolia,Shandong,Jiangsu,Henan and Anhui increased,but the increase was small,while the total factor productivity of grain in Jiangxi,Sichuan,Hunan and Hubei provinces declined.
文摘The increased production efficiency of heat treatable A1 alloys, as the result of applied electromagnetic field during continuous casting process was investigated. The applied frequency of the electromagnetic field (EMF) during the AI alloys continuous casting was changing from 30 Hz to 50 Hz, while some castings were obtained without the EMF influence. The mechanical characterization of continuous casted AI alloys EN AW 2007 and En AW 2024 was done on testing machine Zwick/Roell Z 100. The microstructure of as-cast samples was examined, as well. When the frequency decreases (from 50 Hz to 30 Hz), the grain size decreases as well, what is noticeable through the finer microstructure and its uniformity throughout the cross-section. These results have shown that low frequency electromagnetic field significantly influenced the microstructure and therefore the mechanical properties of as cast ingots. Thus, through improved castings quality, operation time and energy savings, the production efficiency was increased.