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Characterization of Small-Scale Farmers and Assessment of Their Access to Crop Production Information in Selected Counties of Kenya
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作者 Anastasia Mumbi Wahome John B. K. Kiema +1 位作者 Galcano C. Mulaku Isaac Mukoko 《Agricultural Sciences》 2024年第5期565-589,共25页
Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sol... Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sold to bring in some income. Timely decisions on farm practices such as farm preparation and planting are critical determinants of the seasonal outcomes. In Kenya, most small-scale farmers have no reliable source of information that would help them make timely and accurate decisions. County governments have extension officers who are mandated with giving farmers advisory services to farmers but they are not able to reach most farmers due to facilitation constraints. The mode and format of sharing information is also critical since it’s important to ensure that it’s timely, well-understood and usable. This study sought to assess access to geospatial derived and other crop production information by farmers in four selected counties of Kenya. Specific objectives were to determine the profile of small-scale farmers in terms of age, education and farm size;to determine the type of information that is made available to them by County and Sub-County extension officers including the format and mode of provision;and to determine if the information provided was useful in terms of accuracy, timeliness and adequacy. The results indicated that over 80% of the farmers were over 35 years of age and over 56% were male. Majority had attained primary education (34%) or secondary education (29%) and most farmers in all the counties grew maize (71%). Notably, fellow farmers were a source of information (71%) with the frequency of sharing information being mostly seasonal (37%) and when information was available (43%). Over 66% of interviewed farmers indicating that they faced challenges while using provided information. The results from the study are insightful and helpful in determining effective ways of providing farmers with useful information to ensure maximum benefits. 展开更多
关键词 Small scale Farmers FARMERS Crop production Information Services Geospatial Information Information Access
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Dendritic cells derived from pluripotent stem cells:Potential of large scale production 被引量:5
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作者 Yan Li Meimei Liu Shang-Tian Yang 《World Journal of Stem Cells》 SCIE CAS 2014年第1期1-10,共10页
Human pluripotent stem cells(hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, are promising sources for hematopoietic cells due to their unlimited growth capacity and the pluripot... Human pluripotent stem cells(hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, are promising sources for hematopoietic cells due to their unlimited growth capacity and the pluripotency. Dendritic cells(DCs), the unique immune cells in the hematopoietic system, can be loaded with tumor specific antigen and used as vaccine for cancer immunotherapy. While autologous DCs from peripheral blood are limited in cell number, hPSC-derived DCs provide a novel alternative cell source which has the potential for large scale production. This review summarizes recent advances in differentiating hPSCs to DCs through the intermediate stage of hematopoietic stem cells. Step-wise growth factor induction has been used to derive DCs from hPSCs either in suspension cultureof embryoid bodies(EBs) or in co-culture with stromal cells. To fulfill the clinical potential of the DCs derived from hPSCs, the bioprocess needs to be scaled up to produce a large number of cells economically under tight quality control. This requires the development of novel bioreactor systems combining guided EB-based differentiation with engineered culture environment. Hence, recent progress in using bioreactors for hPSC lineage-specific differentiation is reviewed. In particular, the potential scale up strategies for the multistage DC differentiation and the effect of shear stress on hPSC differentiation in bioreactors are discussed in detail. 展开更多
关键词 PLURIPOTENT stem CELLS DENDRITIC CELLS BIOREACTOR HEMATOPOIETIC differentiation Large scale production
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Multidisciplinary design optimization on production scale of underground metal mine 被引量:4
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作者 左红艳 罗周全 +1 位作者 管佳林 王益伟 《Journal of Central South University》 SCIE EI CAS 2013年第5期1332-1340,共9页
In order to ensure overall optimization of the underground metal mine production scale, multidisciplinary design optimization model of production scale which covers the subsystem objective function of income of produc... In order to ensure overall optimization of the underground metal mine production scale, multidisciplinary design optimization model of production scale which covers the subsystem objective function of income of production, safety and environmental impact in the underground metal mine was established by using multidisciplinary design optimization method. The coupling effects from various disciplines were fully considered, and adaptive mutative scale chaos immunization optimization algorithm was adopted to solve multidisciplinary design optimization model of underground metal mine production scale. Practical results show that multidisciplinary design optimization on production scale of an underground lead and zinc mine reflect the actual operating conditions more realistically, the production scale is about 1.25 Mt/a (Lead and zinc metal content of 160 000 t/a), the economic life is approximately 14 a, corresponding coefficient of production profits can be increased to 15.13%, safety factor can be increased to 5.4% and environmental impact coefficient can be reduced by 9.52%. 展开更多
关键词 underground metal mines production scale multidisciplinary design optimization adaptive mutative scale chaosoptimization algorithm immunization
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An intelligent system for calculating the scale of rational,enlarged production of an underground non-ferrous metal mine 被引量:4
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作者 ZHENG Ming-gui CAI Si-jing 《Journal of China University of Mining and Technology》 EI 2008年第2期214-219,共6页
The enlarged production scale of underground non-ferrous metal mines is affected by many uncertain factors difficult to describe mathematically with any level of accuracy.The problem can be solved by a synthesis of ar... The enlarged production scale of underground non-ferrous metal mines is affected by many uncertain factors difficult to describe mathematically with any level of accuracy.The problem can be solved by a synthesis of artificial intelligence.Based on the analysis of the major factors affecting the scale of enlarged production,we first interpreted in detail the design principles and structure of the intelligent system.Secondly,we introduced an ANN subsystem.In order to ensure technological and scale efficien- cies of the training samples for ANN,we filtrated the samples with a DEA method.Finally,we trained the intelligent system,which was proved to be very efficient. 展开更多
关键词 non-ferrous metal mines production scale enlarge intelligent system ANN
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Effects of the Produced Water from a Sour Oilfield in South Kuwait on the Production Tubing
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作者 Feras Al Salem Vijo Poulose +3 位作者 Kazuyuki Kawamura Arata Nakamura Hakim Saibi Thies Thiemann 《Journal of Water Resource and Protection》 2023年第7期358-375,共18页
Kuwaiti oil production faces a growing challenge in the increasing quantities of produced water generated in the production of oil. The high water cut of the produced fluid from the wells and the high salinity of the ... Kuwaiti oil production faces a growing challenge in the increasing quantities of produced water generated in the production of oil. The high water cut of the produced fluid from the wells and the high salinity of the produced water lead to significant degradation of subsurface equipment, specifically the production tubing. Debris generated through the degradation of the inner part of the tubing becomes a constituent of the scaling that deposits in the tubing and blocks the flow of the production fluid, inducing higher maintenance costs. This paper looks at the characteristics of the scaling in regard to the produced water and outlines the economic impact of the produced water induced degradation of the tubing structure. 展开更多
关键词 Produced Water SCALING production Tubing Corrosion SEM-EDS WD-XRF XPS
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An Empirical Study on the Moderate Scale of Food-production-based Family Farm in Guangxi
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作者 Yaogui WU 《Asian Agricultural Research》 2016年第4期22-24,共3页
The moderate scale family farm is the future agricultural business entity in China,and the scale of family farm is a key factor affecting its development.With Guigang City in Guangxi as a point for the study,from the ... The moderate scale family farm is the future agricultural business entity in China,and the scale of family farm is a key factor affecting its development.With Guigang City in Guangxi as a point for the study,from the perspective of maximizing income of rural households,this paper uses production function model to calculate the moderate scale of food-production-based family farm at 5.7 ha,and makes policy recommendations. 展开更多
关键词 FOOD production Family FARM MODERATE scale
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Production of Rubidium Bose-Einstein Condensate in an Optically Plugged Magnetic Quadrupole Trap
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作者 张东方 高天佑 +2 位作者 孔令冉 李凯 江开军 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期120-123,共4页
We experimentally produce the rubidium Bose-Einstein condensate in an optically plugged magnetic quadrupole trap. A far blue-detuned focused laser beam with a wavelength of 532nm is plugged in the center of the magnet... We experimentally produce the rubidium Bose-Einstein condensate in an optically plugged magnetic quadrupole trap. A far blue-detuned focused laser beam with a wavelength of 532nm is plugged in the center of the magnetic quadrupole trap to increase the number of trapped atoms and to suppress the heating. An rf evaporative cooling in the magneto-optical hybrid trap is applied to decrease the atom temperature into degeneracy. The atom number of the condensate is 1.2(0.4)× 10^5 and the temperature is below lOOnK. We also study characteristic behaviors of the condensate, such as phase space density, condensate fraction and anisotropic expansion. 展开更多
关键词 of is BEC in production of Rubidium Bose-Einstein Condensate in an Optically Plugged Magnetic Quadrupole trap
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Kenyan Counties Geospatial Data Knowledge to Monitor Crop Production
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作者 Anastasia Mumbi Wahome John B. K. Kiema Galcano C. Mulaku 《Journal of Geographic Information System》 2023年第6期629-651,共23页
Climate change effects have had negative effects on most farmers, both small and large-scale, with weather patterns increasingly becoming unpredictable, such that farmers are unable to plan well for their farming, res... Climate change effects have had negative effects on most farmers, both small and large-scale, with weather patterns increasingly becoming unpredictable, such that farmers are unable to plan well for their farming, resulting in reduced harvests and sometimes losses for farmers. Better availability of information such as weather patterns, suitable crops, nutrient requirements based on soil types and conditions would greatly alleviate these challenges. While geospatial information is being developed and improved continuously by researchers, its accessibility and use by the counties has not been established and cannot be identified as contributing to better crop production outcomes. The aim of this study, therefore, was to assess the awareness and status of geospatial data availability and use for crop production, and the level of the relevant capacities, both human and infrastructural, in selected Counties of Kenya. A survey was conducted in the four counties of Vihiga, Kilifi, Wajir and Nyeri and key informant interviews were conducted with both management and technical County Agricultural Officers, as well as sub-county agricultural extension officers. From the results of the survey, out of the four counties, only one has adequate infrastructure in terms of hard-ware, software and connectivity to conduct useful geospatial data acquisition and processing. While most indicated awareness of the existence of geospatial data, limited resources, low skills and knowledge have restricted any meaningful sourcing of and access to data, with only 38% moderately or highly skilled in acquisition, 48% in processing and 57% in interpretation and use of geospatial data. The study concludes that moderate skills and capacities available within the counties have considerable potential to make use the available geospatial data to inform farmers accordingly and improve their farming outcomes. 展开更多
关键词 Geospatial Data Crop production AGRICULTURE FARMERS Small-scale Farmers
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Production of Degenerate Fermi Gases of ~6Li Atoms in an Optical Dipole Trap
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作者 Xiang-Chuan Yan Da-Li Sun +3 位作者 Lu Wang Jing Min Shi-Guo Peng Kai-Jun Jiang 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第5期67-71,共5页
We report the experimental production of degenerate Fermi gases of 6 Li atoms in an optical dipole trap.The gray-molasses technique is carried out to decrease the atomic temperature to 57 μK,which facilitates the eff... We report the experimental production of degenerate Fermi gases of 6 Li atoms in an optical dipole trap.The gray-molasses technique is carried out to decrease the atomic temperature to 57 μK,which facilitates the efficient loading of cold atoms into the optical dipole trap.The Fermi degeneracy is achieved by evaporative cooling of a two-spin mixture of ~6 Li atoms on the Feshbach resonance.The degenerate atom number per spin is 3.5×10^(4),and the reduced temperature T/T_F is as low as 0.1,where T_F is the Fermi temperature of the non-interacting Fermi gas.We also observe the anisotropic expansion of the atom cloud in the strongly interacting regime. 展开更多
关键词 RED production of Degenerate Fermi Gases of Atoms in an Optical Dipole trap
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Study on the Production Benefit of Large-scale Tobacco Growers
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作者 Shunyou LU Qinggao CHEN +2 位作者 Ting LEI Yuanhui WANG Huizhong LIU 《Asian Agricultural Research》 2014年第5期8-10,共3页
The tobacco growers with the growing area of greater than or equal to 100 mu,have become an important subject of tobacco production in Weng'an County of Guizhou Province. Regulating and developing the production a... The tobacco growers with the growing area of greater than or equal to 100 mu,have become an important subject of tobacco production in Weng'an County of Guizhou Province. Regulating and developing the production and business activities of large-scale tobacco growers, plays an important role in stabilizing tobacco production,reducing costs and increasing efficiency in Weng'an County. Through the field survey of large-scale growers' production activities,this article analyzes the input and output levels,and explores the key factors influencing benefit, in order to provide a basis for further regulating the tobacco growing practices and improving the flue-cured tobacco production benefit. 展开更多
关键词 LARGE-scale TOBACCO GROWERS production BENEFIT KEY
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Impact of Small-scale Production Mode on Citrus Industry of Hunan Province,China——Based on the Investigation on Citrus Industry in Shimen County
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作者 HU Zhi-dan1,WANG Kui-wu2,BO Xin1,TAN Jie2 1.College of Humanities,Hunan Agricultural University,Changsha 410128,China 2.Department of Scientific Research,Hunan Agricultural University,Changsha 410128,China 《Asian Agricultural Research》 2010年第3期38-40,共3页
Small-scale farmer is defined by the domestic and foreign experts and scholars.They point out that since the fragmentation of production and the diseconomy of scale in small-scale farmer is inconsistent with the chara... Small-scale farmer is defined by the domestic and foreign experts and scholars.They point out that since the fragmentation of production and the diseconomy of scale in small-scale farmer is inconsistent with the characteristics of scale and technology of modern agricultural production,it is necessary to eliminate the adverse effects of existing mode in order to provide theoretical references for the relevant researches.Citrus industry in Shimen County,Hunan Province,China is introduced from the aspects of natural geographical condition and socio-economic benefit.Impact of small-scale production mode on citrus production in Shimen County is discussed.Firstly,blindness of small-scale production is the main reason leading to overproduction of citrus.Secondly,small-scale production mode has limitation on the acceptance of new technologies,restricts the operation of geographical trademark,and constraints the enthusiasm of enterprises in entering the agricultural field.Finally,suggestions are put forward,such as encouraging the circulation of rural land,improving the organization degree of farmers,changing the work function of grass-roots government and perfecting the agricultural financial credit system. 展开更多
关键词 SMALL-scale production MODE CITRUS INDUSTRY Geogra
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Sustainable Potato Production in the Mountain Area of Ecuador, an Approach to Increase Productivity with Small Scale Farmers
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作者 Alicia Villavicencio Chang Hwan Park +16 位作者 Kangjin Cho Rona Bae Diego Peñ aherrera Gabriela Narváez Victoria López José Camacho Jovanny Suquillo Fausto Yumisaca Cesar Asaquibay María Nieto David Ortega Verónica Quimbiamba Cristian Torres Edwin Naranjo Stalin Cuenca Ricardo Alvarez 《Agricultural Sciences》 CAS 2022年第10期1080-1090,共11页
Ecuador potato crop is family based production system. Potato production has two roles in their economy, the first is providing food for their families and the second is a source of income for the household. However s... Ecuador potato crop is family based production system. Potato production has two roles in their economy, the first is providing food for their families and the second is a source of income for the household. However small scale farmers have limited access to local markets and most of the sales are through intermediates’ who purchase directly in the field at the lowest price possible. Potato production challenges for the small-scale farmers are among others availability of quality potato seed, direct sales, purchase of agrochemical inputs to maintain their crops and lack of education. In 2021, only 4% of potato farmers used certified seed. Potato yield is still low around 16.1 t&#183;ha<sup>-1</sup>, in the last 10 years the total potato cultivated area was reduced by at least 50%. The farmers produce “Bokashi” and other organic fertilizer and these are effective to improve soil fertility and plant health. Homemade bio-pesticides reduce agrochemical pesticides. The Decision Support System (DSS) is a handheld device to control late blight, minimizes fungicide applications and improve fungicide rotation. In 2018 Candidatus Liberibacter solanacearum (Lso), the causal agent of zebra chip, and its vector, the potato psyllid Bactericera cockerelli, together created havoc for farmers and researchers. Promotion of early potato varieties INIAP—Libertad is an alternative to lower the impact of this newest pest. 展开更多
关键词 POTATO Yield Small-scale Farmers Agro-Ecological production Quality Seed
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Wear Resistance of CO_2 Corrosion Product Scale Formed at High Temperature 被引量:6
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作者 LIN Guan-fa ZHENG Mao-sheng +1 位作者 BAI Zhen-quan FENG Yao-rong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第5期47-52,共6页
To investigate the correlation between structure characteristics and wear resistance of CO2 corrosion product scales at high temperature and high pressure, an autoclave was used to prepare CO2 corrosion product scales... To investigate the correlation between structure characteristics and wear resistance of CO2 corrosion product scales at high temperature and high pressure, an autoclave was used to prepare CO2 corrosion product scales on N80 steel in carbon dioxide corrosion environment. The correlation between wear resistance of the scales and many other factors, such as temperature, pressure, morphology, structure, velocity of fluid medium, sand grain size, and so on, was comparatively analyzed by a self assembled wear device, and the scale morphologies before or after being worn were observed by scanning electron microscope (SEM). And then the surface grain size and thickness of scale were measured. The results showed that the cross-section of the corrosion scale was of a double-layer structure, the outer layer of which was composed of regular crystals, whereas the inner layer was a thin scale of fine grains. The outer grain size and thickness of scale varied with temperature, and the initial wear loss was consistent with the surface grain size; at the same time, the total wear loss corresponded to the thickness of scale. Compared to wear resist- ance in different depths of the scale, it was found that the structure of scale was a double-layer structure in cross-section, and the wear resistance of inner layer was better than that of the outer layer; the closer the scale to the matrix, the greater was the wear resistance of scale; and the larger the size or the higher the rotary speed of solid grain in multiphase flowing medium, the more was the wear loss of scale. 展开更多
关键词 CO2 corrosion corrosion product scale WEAR N80 steel MORPHOLOGY structure
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Simultaneous identification and quantification of tetrodotoxin in fresh pufferfish and pufferfish-based products using immunoaffinity columns and liquid chromatography/quadrupole-linear ion trap mass spectrometry 被引量:4
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作者 郭萌萌 吴海燕 +5 位作者 江涛 谭志军 赵春霞 郑关超 李兆新 翟毓秀 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第4期883-893,共11页
In this study, we established a comprehensive method for simultaneous identification and quantification of tetrodotoxin (TTX) in fresh pufferfish tissues and pufferfish-based products using liquid chromatography/qua... In this study, we established a comprehensive method for simultaneous identification and quantification of tetrodotoxin (TTX) in fresh pufferfish tissues and pufferfish-based products using liquid chromatography/quadrupole-linear ion trap mass spectrometry (LC-QqLIT-MS). TTX was extracted by 1% acetic acid-methanol, and most of the lipids were then removed by freezing lipid precipitation, followed by purification and concentration using immunoaffinity columns (IACs). Matrix effects were substantially reduced due to the high specificity of the IACs, and thus, background interference was avoided. Quantitation analysis was therefore performed using an external calibration curve with standards prepared in mobile phase. The method was evaluated by fortifying samples at 1, 10, and 100 ng/g, respectively, and the recoveries ranged from 75.8%--107%, with a relative standard deviation of less than 15%. The TTX calibration curves were linear over the range of 1-1 000 ~tg/L, with a detection limit of 0.3 ng/g and a quantification limit of 1 ng/g. Using this method, samples can be further analyzed using an information- dependent acquisition (IDA) experiment, in the positive mode, from a single liquid chromatography-tandem mass spectrometry injection, which can provide an extra level of confirmation by matching the full product ion spectra acquired for a standard sample with those from an enhanced product ion (EPI) library. The scheduled multiple reaction monitoring method enabled TTX to be screened for, and TTX was positively identified using the IDA and EPI spectra. This method was successfully applied to analyze a total of 206 samples of fresh pufferfish tissues and pufferfish-based products. The results from this study show that the proposed method can be used to quantify and identify TTX in a single run with excellent sensitivity and reproducibility, and is suitable for the analysis of complex matrix pufferfish samples. 展开更多
关键词 TETRODOTOXIN fresh pufferfish pufferfish-based product immunoaffinity column liquidchromatography/quadrupole-linear ion trap mass spectrometry
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Technical efficiency and its determinants in China's hog production 被引量:9
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作者 TIAN Xu SUN Fei-fei ZHOU Ying-heng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第6期1057-1068,共12页
China's hog production is undergoing a great transformation due to the soaring demand and changing raising system. Regarding the essential role of pork in Chinese diet, a systematic analysis on the productivity and e... China's hog production is undergoing a great transformation due to the soaring demand and changing raising system. Regarding the essential role of pork in Chinese diet, a systematic analysis on the productivity and efficiency of hog production can provide significant implications for policy makers. This paper investigates the productivity and efficiency of hog production and the determinants of technical efficiency in China using a household level panel data(2004–2010). A stochastic frontier translog production function with scaling property in inefficiency term is adopted for hog production analysis, and the determinants of technical efficiency are incorporated in a one-step estimation using maximum likelihood estimation. Our results show that the average technical efficiency of hog production in China is 0.5914. More importantly, we find that specialized farmers have higher technical efficiency than others, and technical efficiency in the eastern region is higher than that in Central and West China. 展开更多
关键词 frontier specialized household stochastic productivity panel raising husbandry scaling incorporated
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Empirical Research on E-commerce to Increase the Scale of Agricultural Products Trade: Taking Guangxi Hezhou Zhengfeng Modern Agriculture Co.,Ltd. as an Example 被引量:2
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作者 Changliang PAN Jinfang LI 《Asian Agricultural Research》 2020年第2期8-10,共3页
Agriculture is the foundation of the national economy.The periodicity of agricultural product output and prices,the asymmetry of information between buyers and sellers,and the inherent characteristics of small scale,h... Agriculture is the foundation of the national economy.The periodicity of agricultural product output and prices,the asymmetry of information between buyers and sellers,and the inherent characteristics of small scale,high cost,and low profit have caused slow sales,which greatly hurt the enthusiasm of farmers to develop production and endanger social stability.Constructing an informationized and commercialized trading platform and an information sharing platform through e-commerce and establishing related systems and supervision mechanisms will help to promote the rapid growth of agricultural product sales.Research has shown that in the field of agricultural circulation,e-commerce has a significant effect on increasing the scale of agricultural trade. 展开更多
关键词 E-COMMERCE Agricultural product TRADE scale Case study
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Review of chip-scale atomic clocks based on coherent population trapping 被引量:10
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作者 汪中 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期47-58,共12页
Research on chip-scale atomic clocks (CSACs) based on coherent population trapping (CPT) is reviewed. The back- ground and the inspiration for the research are described, including the important schemes proposed t... Research on chip-scale atomic clocks (CSACs) based on coherent population trapping (CPT) is reviewed. The back- ground and the inspiration for the research are described, including the important schemes proposed to improve the CPT signal quality, the selection of atoms and buffer gases, and the development of micro-cell fabrication. With regard to the re- liability, stability, and service life of the CSACs, the research regarding the sensitivity of the CPT resonance to temperature and laser power changes is also reviewed, as well as the CPT resonance's collision and light of frequency shifts. The first generation CSACs have already been developed but its characters are still far from our expectations. Our conclusion is that miniaturization and power reduction are the most important aspects calling for further research. 展开更多
关键词 chip-scale atomic clock coherent population trapping
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Efficiency Evaluation of Effect of Direct Grain Subsidy Policy on Performance of Rice Production 被引量:1
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作者 Liyun LU Guanqiao LI 《Asian Agricultural Research》 2017年第4期11-15,共5页
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
关键词 Direct grain subsidy Rice production performance scale efficiency Pure technology efficiency DEA
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Robust Corner Detection Based on Multi-scale Curvature Product in B-spline Scale Space 被引量:3
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作者 WANG Yu-Zhu YANG Dan ZHANG Xiao-Hong 《自动化学报》 EI CSCD 北大核心 2007年第4期414-417,共4页
这份报纸在 B 花键弯曲规模空间的框架论述一种多尺度的弯曲产品角落察觉技术。规模产品功能在不同规模从轮廓的弯曲产品被导出。角落被 thresholding 作为本地最大值构造越过几规模的弯曲产品结果。通过规模产品,本地化精确性和察觉... 这份报纸在 B 花键弯曲规模空间的框架论述一种多尺度的弯曲产品角落察觉技术。规模产品功能在不同规模从轮廓的弯曲产品被导出。角落被 thresholding 作为本地最大值构造越过几规模的弯曲产品结果。通过规模产品,本地化精确性和察觉表演能显著地以 CNN 标准被改进。实验也证明那个建议方法显示出坚韧性到高频率细节并且提供有希望的察觉结果。 展开更多
关键词 曲线 刻度 自动化技术 小波
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Agricultural Production Efficiency of Chongqing Based on DEA
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作者 CHEN Hong-yue,XIAO Hong-an College of Economics and Management,Sichuan Agricultural University,Ya’an 625014,China 《Asian Agricultural Research》 2010年第3期51-53,共3页
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
关键词 AGRICULTURAL production EFFICIENCY DEA model scale
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