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Agricultural extension approach: evidence from an Integrated Soil Fertility Management Project in Ethiopia

Gerba LETA, Steffen SCHULZ, Girum GETACHEW ALEMU

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 427-439 doi: 10.15302/J-FASE-2020331

摘要：

Agricultural extension is an approach to rural development and agricultural transformation in which training, demonstration and technology transfer are key to reducing rural poverty, ensuring food security, and sustainably managing natural resources. During recent decades, different extension approaches have been tested and validated by the Ethiopian government and non-governmental organizations to stimulate in the agricultural extension system (AES). The most recent was a German-funded project entitled “Integrated Soil Fertility Management Project” (ISFM ), which employed a novel approach to piloting and upscaling proven technology and best practice. The purpose of this study was to analyze and document the modalities of ISFM and illustrate its effects on technology uptake and dissemination. The study used a mixed methods approach to collect data. ATLAS.ti and SPSS were used for data management and analysis. Farmer Research and Extension Groups and Farmer Field Schools were found to be central to the participation process. Also, the ISFM was found to aid technology transfer and helped to increase grain and residue yields as well as farmer livelihoods. Based on these empirical findings, it is argued that the ISFM approach and technology should be integrated and institutionalized in the mainstream AES in order to promote their extensive application.

关键词： Ethiopia     Farmer Field School     Farmer Research and Extension Group     governance     institutionalization     ISFM+ ambassador     participation    

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SOIL CARBON CHECK: A TOOL FOR MONITORING AND GUIDING SOIL CARBON SEQUESTRATION IN FARMER FIELDS

《农业科学与工程前沿（英文）》 2023年 第10卷 第2期   页码 248-261 doi: 10.15302/J-FASE-2023499

摘要：

● Establishment of a rapid tool for monitoring soil carbon sequestration in farmer fields.

关键词： 4 per 1000 initiative     carbon sequestration     climate action     farmer fields     SDG13     soil organic carbon     soil testing    

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ENTREPRENEURIAL OPPORTUNITY, VALUE EVOLUTION, AND ORGANIZATIONAL INTEGRATION OF PROFESSIONAL FARMER ENTREPRENEURSHIP

《农业科学与工程前沿（英文）》 2023年 第10卷 第1期   页码 135-148 doi: 10.15302/J-FASE-2022464

摘要：

● The choice of a modern agriculture project was found to be rational for professional farmers to reduce interference from non-market factors. The success of this project is due to its capacity to successfully fill the structural hole in the market transaction network.

关键词： Benefit-linked mechanism     featured agriculture     organizational integration     professional farmers     rural cooperative     structural hole theory    

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Russian school of the theory and geometry of gearing: Its origin and golden period (1935 --1975)

Dmitry BABICHEV,Sergey LAGUTIN,Natalya BARMINA

《机械工程前沿（英文）》 2016年 第11卷 第1期   页码 44-59 doi: 10.1007/s11465-015-0360-z

摘要：

During the second half of the twentieth century, Soviet scientists were among the world leaders in the theory and geometry of gearing or the theoretical fundamentals of designing gears and gear-cutting tools. The authors of the current paper review works related to the development of the theory of gearing (TG) written in Russian from the mid-1930s to the present. Overall, the review covers more than 400 publications of nearly 200 authors (among more than 1000 studied works). This review involves some works on gear strength and accuracy to attract more experts.

This paper presents a short list of works from the seventeenth century to the nineteenth century and discusses the basic concepts of the TG. This paper also includes a review of more than 160 papers in Russian for the period of 1935–1975, which is the “golden age” of the TG. The main features and achievements during this period are also considered.

The distinctive feature of this review is the use of diagrams that visually present TG experts and the dates and themes of their published works. The diagrams also show the following aspects: 1) The most popular and important themes in a specific period, 2) the most important publications on the themes of interest to readers, and 3) the direction of the works and scope of interests of every researcher.

关键词： theory of gearing (TG)     gear geometry     generating surface     gear synthesis     gear analysis    

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AGRICULTURAL GREEN DEVELOPMENT IN THE ERHAI LAKE BASIN—THE WAY FORWARD

《农业科学与工程前沿（英文）》 2023年 第10卷 第4期   页码 510-517 doi: 10.15302/J-FASE-2023524

摘要：

Pollution of high-altitude lake basins by agriculture and rural activities, and the control of this pollution, have received increasing attention from academic research and government policy in China. Series of restrictions and regulations have been implemented to protect the surface water quality. These restrictions and regulations have greatly impacted and transformed the agricultural systems and rural livelihoods surrounding these lake basins. Using Erhai Lake basin in Yunnan Province as a case study, three main challenges were identified for concurrently decreasing pollution in the lake and increasing farmer income. It is contended that scientifically-sound environmental protection policies and agricultural green development practices are key to reversing the current situation. This will help to protect the lake from pollution while smallholder farmers will be able to produce healthy food in an environmentally sustainable manner, and with a fair remuneration for all the services farmers provide to the society.

关键词： agriculture     farmer income     nitrogen     phosphorus     water pollution    

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国产农机装备质量评价研究——基于华中地区农户调查数据的分析

周晶,青平

《中国工程科学》 2019年 第21卷 第5期   页码 60-66 doi: 10.15302/J-SSCAE-2019.05.019

摘要：

提高国产农机装备质量是我国农机制造由大到强的必要条件。本文在总结我国农机装备制造业发展现状和存在问题的基础上，突出实证研究，利用来自华中地区的农户调查数据，从硬件质量、适用性和操作便利性、作业效果三方面考察农户对国产农机装备质量的主观评价。结果显示，农机户对国产大中型农机装备钢材质量、发动机质量、耗油量和故障频率的满意度显著低于非国产品牌；不足一半的农机户对国内外大中型农机装备地块匹配度、驾驶员匹配度、遮阳挡雨效果持满意态度；农户对国产农机装备作业速度、作业无遗漏、节省要素的满意度偏低。立足现状、着眼长远，提出组建关键零部件克难攻坚“国家队”、搭建以企业为主体的长效技术创新体系、抢抓智能化和绿色化农机装备研发、重构高等院校农机学科体系等对策建议。

关键词： 国产农机     质量评价     农户调查     华中地区    

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Effectiveness of preventive medicine education and its determinants among medical students in Malaysia

null

《医学前沿（英文）》 2016年 第10卷 第1期   页码 91-100 doi: 10.1007/s11684-016-0428-0

摘要：

Preventive medicine has been incorporated in the medical school curriculum, but its effectiveness and the factors that affect it are yet to be widely looked into in the context of Malaysia. We aimed to measure the familiarity with, perception about the importance to learn, and the ability to practice preventive medicine as well as its determinants among the medical students in Malaysia. Thus, a cross sectional study was conducted through an anonymous online survey among 387 randomly selected final year medical students of four large public medical schools in Malaysia from March to September 2014. Of the total sample, only 340 (response rate 87.8%) gave a written informed consent and took part in the survey. The familiarity of the sample with preventive medicine was measured in 19 preventive medicine areas, and their perception about the importance of preventive medicine and their ability to practice it were gauged on a Likert scale (low score indicates disagreement and high indicates agreement). Descriptive statistical analysis was performed, followed by logistic regression. The mean age of the respondents was 23.7 (SD 0.77) years, and 61.2% (n = 208) of them were females. Results showed that 22.9% of the sample (n= 78) had a low familiarity with preventive medicine, whereas 76.8% (n = 261) had a high familiarity. The study sample specified that among all the preventive medicine subjects, screening and control as well as smoking cessation and immunization are “extremely important to learn.” In univariable analysis, being a female, medical school, family size, and perception about the importance to learn preventive medicine were associated with the ability to practice it. In multivariable analysis, the perception towards the importance to learn preventive medicine was the only significant determinant: aOR (adjusted odds ratio) for those who “agreed” 17.28 (95% CI aOR 4.44 – 67.26, P<0.001) and for “strongly agreed” 35.87 (95% CI aOR 8.04 – 159.87, P<0.001). Considering these findings, the familiarity of medical students with preventive medicine should be increased. The perception about the importance to learn preventive medicine is a strong determinant for the ability to practice it.

关键词： preventive medicine     medical school     medical students    

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三谈创建现代管理科学中国学派的若干问题：四条定义与三点建议

刘人怀,孙东川,孙凯

《中国工程科学》 2009年 第11卷 第8期   页码 18-23

摘要：

探讨了管理领域的一些基本概念与基本问题,明确提出4条定义：a.管理活动是人类的第二类活动，它为第一类活动（作业活动）提供服务；b.组织的管理活动称为管理工作，这是组织中的一大类工作；c.组织委派某些人员专门从事管理工作，这些人员就成为管理工作者；d.管理科学是研究管理活动规律与做好管理工作的全部知识的总和，是一个内容丰富的知识体系。鉴于管理与管理科学这两个术语的中英文含义差别比较大，造成中国学术界在管理科学研究中的歧义和混乱，笔者梳理出3点建议。

关键词： 管理     管理活动     管理工作     管理科学     现代管理科学的中国学派     话语权    

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Recent progress in electric-field assisted combustion: a brief review

《能源前沿（英文）》 2022年 第16卷 第6期   页码 883-899 doi: 10.1007/s11708-021-0770-z

摘要： The control of combustion is a hot and classical topic. Among the combustion technologies, electric-field assisted combustion is an advanced techno-logy that enjoys major advantages such as fast response and low power consumption compared with thermal power. However, its fundamental principle and impacts on the flames are complicated due to the coupling between physics, chemistry, and electromagnetics. In the last two decades, tremendous efforts have been made to understand electric-field assisted combustion. New observations have been reported based on different combustion systems and improved diagnostics. The main impacts, including flame stabilization, emission reduction, and flame propagation, have been revealed by both simulative and experimental studies. These findings significantly facilitate the application of electric-field assisted combustion. This brief review is intended to provide a comprehensive overview of the recent progress of this combustion technology and further point out research opportunities worth investigation.

关键词： electric field     combustion     flame stabilization     emission reduction     flame propagation    

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A MATLAB code for the material-field series-expansion topology optimization method

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 607-622 doi: 10.1007/s11465-021-0637-3

摘要： This paper presents a MATLAB implementation of the material-field series-expansion (MFSE) topo-logy optimization method. The MFSE method uses a bounded material field with specified spatial correlation to represent the structural topology. With the series-expansion method for bounded fields, this material field is described with the characteristic base functions and the corresponding coefficients. Compared with the conventional density-based method, the MFSE method decouples the topological description and the finite element discretization, and greatly reduces the number of design variables after dimensionality reduction. Other features of this method include inherent control on structural topological complexity, crisp structural boundary description, mesh independence, and being free from the checkerboard pattern. With the focus on the implementation of the MFSE method, the present MATLAB code uses the maximum stiffness optimization problems solved with a gradient-based optimizer as examples. The MATLAB code consists of three parts, namely, the main program and two subroutines (one for aggregating the optimization constraints and the other about the method of moving asymptotes optimizer). The implementation of the code and its extensions to topology optimization problems with multiple load cases and passive elements are discussed in detail. The code is intended for researchers who are interested in this method and want to get started with it quickly. It can also be used as a basis for handling complex engineering optimization problems by combining the MFSE topology optimization method with non-gradient optimization algorithms without sensitivity information because only a few design variables are required to describe relatively complex structural topology and smooth structural boundaries using the MFSE method.

关键词： MATLAB implementation     topology optimization     material-field series-expansion method     bounded material field     dimensionality reduction    

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Field test on temperature field and thermal stress for prestressed concrete box-girder bridge

Baoguo CHEN, Rui DING, Junjie ZHENG, Shibiao ZHANG

《结构与土木工程前沿（英文）》 2009年 第3卷 第2期   页码 158-164 doi: 10.1007/s11709-009-0002-9

摘要： A field test was conducted to investigate the distribution of temperature field and the variation of thermal stress for a prestressed concrete (PC) box-girder bridge. The change of hydration heat temperature consists of four periods: temperature rising period, constant temperature period, rapid temperature fall period and slow temperature fall period. The peak value of hydration heat temperature increases with the increasing casting temperature of concrete; the relation between them is approximately linear. According to field tests, the thermal stress incurred by hydration heat may induce temperature cracks on the PC box-girder. Furthermore, the nonlinear distribution of temperature gradient and the fluctuation of thermal stress induced by exposure to sunlight were also obtained based on continuous in-situ monitoring. Such results show that the prevailing Chinese Code (2004) is insufficient since it does not take into account the temperature gradient of the bottom slab. Finally, some preventive measures against temperature cracks were proposed based on related studies. The conclusions can provide valuable reference for the design and construction of PC box-girder bridges.

关键词： box-girder bridge     field test     hydration heat     temperature field     temperature gradient     thermal stress    

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Energy field-assisted high-speed dry milling green machining technology for difficult-to-machine metal

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0744-9

摘要： Energy field-assisted machining technology has the potential to overcome the limitations of machining difficult-to-machine metal materials, such as poor machinability, low cutting efficiency, and high energy consumption. High-speed dry milling has emerged as a typical green processing technology due to its high processing efficiency and avoidance of cutting fluids. However, the lack of necessary cooling and lubrication in high-speed dry milling makes it difficult to meet the continuous milling requirements for difficult-to-machine metal materials. The introduction of advanced energy-field-assisted green processing technology can improve the machinability of such metallic materials and achieve efficient precision manufacturing, making it a focus of academic and industrial research. In this review, the characteristics and limitations of high-speed dry milling of difficult-to-machine metal materials, including titanium alloys, nickel-based alloys, and high-strength steel, are systematically explored. The laser energy field, ultrasonic energy field, and cryogenic minimum quantity lubrication energy fields are introduced. By analyzing the effects of changing the energy field and cutting parameters on tool wear, chip morphology, cutting force, temperature, and surface quality of the workpiece during milling, the superiority of energy-field-assisted milling of difficult-to-machine metal materials is demonstrated. Finally, the shortcomings and technical challenges of energy-field-assisted milling are summarized in detail, providing feasible ideas for realizing multi-energy field collaborative green machining of difficult-to-machine metal materials in the future.

关键词： difficult-to-machine metal material     green machining     high-speed dry milling     laser energy field-assisted milling     ultrasonic energy field-assisted milling     cryogenic minimum quantity lubrication energy field-assisted milling    

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Temperature field simulation of laser homogenizing equipment

Juanjuan WANG, Yunshan WANG, Fudong ZHU

《机械工程前沿（英文）》 2009年 第4卷 第1期   页码 49-52 doi: 10.1007/s11465-009-0005-1

摘要： The laser homogenizing equipment was devised using the ring scanning principle. Its working principle is explained. A laser scanning ring facula is obtained when the laser beam goes through the equipment’s optical system rotating with high-frequency. The scanning ring facula’s mathematic model is established based on the temperature field’s superposing principle. The ring facula’s light intensity distribution and temperature distribution characteristics are achieved by simulating its temperature field. By studying the effect of parameters on the temperature field, the best parameter can be found. Results show that favorable temperature distribution characteristics can be attained by choosing appropriate parameters, and even the thermal effect can be realized by utilizing the circumference power compensating for the heat exchange lost in the horizontal direction. The uniform hardness layer and better process quality can be attained using the ring facula optimized for metal laser heat treatment.

关键词： laser homogenizing technology     laser scanning ring facula     temperature field    

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Sulige Gas Field super project

Wenrui HU, Jingwei BAO, Pengcheng JI

《工程管理前沿（英文）》 2017年 第4卷 第3期   页码 379-384 doi: 10.15302/J-FEM-2017107

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The influencing factors of the WTP for the risk reduction of chemical industry accidents in China

Lei HUANG, Zhijuan SHAO, Weiliang BAO, Bailing DUAN, Jun BI, Zengwei YUAN

《环境科学与工程前沿（英文）》 2012年 第6卷 第6期   页码 860-868 doi: 10.1007/s11783-012-0467-y

摘要： To explore the factors that influence respondents’ willingness to pay (WTP) for the risk reduction of chemical industry accidents, a questionnaire survey combined with contingent valuation and psychometric paradigm methods were conducted in the city of Yancheng, Jiangsu Province, China. Both traditional socioeconomic variables and perceived characteristics of the hazards were considered in this study, and a Tobit model was used to find the factors influencing WTP under three risk reduction scenarios. The results showed that three demographic characteristics, , , and , significantly affected the WTP for chemical risk reduction. In addition, three extracted public risk perception factors, , , and , also strongly affected the WTP. The mean WTP value increased as the magnitude of the risk reduction increased. The number of factors influencing the WTP decreased as the reduction level improved, and only the factor had a significant influence on the WTP for a higher level (80%) of risk reduction. The cost for chemical safety management of Yancheng was calculated, and the optimized risk reduction level was determined. These findings can assist governments and policy makers to formulate suitable strategies for risk control, to reach target groups of people to develop effective communication, and to provide specific references for the best investment for the security of local residents.

关键词： risk perception     willingness to pay     contingent valuation method     risk management school of the environment    

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标题 作者 时间 类型 操作

Agricultural extension approach: evidence from an Integrated Soil Fertility Management Project in Ethiopia

Gerba LETA, Steffen SCHULZ, Girum GETACHEW ALEMU

期刊论文

SOIL CARBON CHECK: A TOOL FOR MONITORING AND GUIDING SOIL CARBON SEQUESTRATION IN FARMER FIELDS

期刊论文

ENTREPRENEURIAL OPPORTUNITY, VALUE EVOLUTION, AND ORGANIZATIONAL INTEGRATION OF PROFESSIONAL FARMER ENTREPRENEURSHIP

期刊论文

Russian school of the theory and geometry of gearing: Its origin and golden period (1935 --1975)

Dmitry BABICHEV,Sergey LAGUTIN,Natalya BARMINA

期刊论文

AGRICULTURAL GREEN DEVELOPMENT IN THE ERHAI LAKE BASIN—THE WAY FORWARD

期刊论文

国产农机装备质量评价研究——基于华中地区农户调查数据的分析

周晶,青平

期刊论文

Effectiveness of preventive medicine education and its determinants among medical students in Malaysia

null

期刊论文

三谈创建现代管理科学中国学派的若干问题：四条定义与三点建议

刘人怀,孙东川,孙凯

期刊论文

Recent progress in electric-field assisted combustion: a brief review

期刊论文

A MATLAB code for the material-field series-expansion topology optimization method

期刊论文

Field test on temperature field and thermal stress for prestressed concrete box-girder bridge

Baoguo CHEN, Rui DING, Junjie ZHENG, Shibiao ZHANG

期刊论文

Energy field-assisted high-speed dry milling green machining technology for difficult-to-machine metal

期刊论文

Temperature field simulation of laser homogenizing equipment

Juanjuan WANG, Yunshan WANG, Fudong ZHU

期刊论文

Sulige Gas Field super project

Wenrui HU, Jingwei BAO, Pengcheng JI

期刊论文

The influencing factors of the WTP for the risk reduction of chemical industry accidents in China

Lei HUANG, Zhijuan SHAO, Weiliang BAO, Bailing DUAN, Jun BI, Zengwei YUAN

期刊论文