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FEM analysis of workpiece curvature influence on groove deformation during plough process

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Transactions of Nonferrous Metals Society of China 2012年第7期22卷 1738-1743页

作者：陆龙生刘晓辰汤勇袁冬华南理工大学表面功能结构先进制造广东普通高校重点实验室广州510640

To investigate the workpiece curvature influence on groove deformation,numerical studies with curvature varying from negative to positive were conducted on copper *** deformations were analyzed,including groove geometry,effective stress distribution and plough *** curled groove shape whose workpiece curvature was 0.133 mm-1 was validated by ***,a series of geometry models with various curvatures were introduced to analyze the change of groove *** results show that positive curvatures influence groove deformation more intensively than negative or zero *** is mainly due to the action of the tool forming face during plough process.

关键词： plough workpiece curvature microgroove microchannel finite element method

Design and Experiment of 1LFQ-325 Pneumatic Reversible plough

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Asian Agricultural Research 2013年第1期5卷 76-78,82页

作者： Xuan ZHENG Xuefeng CHEN Chaomin QIN Li JIAbo JIA Machinery and Equipment Institute of Xinjiang Academy of Agricultural Reclamation Sciences Xinjiang Tianzhen Farm and Pasture Machinery Manufacturer

A pneumatic reversible plough is developed, which complements to the tractor of 25.7-36.8 *** plough adopts the cylinder as reversing mechanism between the right and left plough bodies, and the cylinder can substitute the mechanical reversing mechanism. The pneumatic turnover allows the plough to be operated easily and turned over flexibly. Field experiment results show that indicators of plough performance meet the requirements of the relevant national standards.

关键词： Pneumatic Reversible plough Design Experiment

Schering—plough公司—“着凉了”

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遗传工程 1983年第4期 51-51页

作者：孙巍

Schering—plough公司是少数几家将其未来赌注于生物工学制药公司之一,它的资金不久也许会有所下降。美国商行用遗传工程方法生产的第一种药物一干扰素,予计于1984年底投放市场。最近的临床试验表明,这种新药也许不是象该公司所希望那... 详细信息

Schering—plough公司是少数几家将其未来赌注于生物工学制药公司之一,它的资金不久也许会有所下降。美国商行用遗传工程方法生产的第一种药物一干扰素,予计于1984年底投放市场。最近的临床试验表明,这种新药也许不是象该公司所希望那样的摇钱树。

关键词：工学 Schering plough

Effects of bionic non-smooth surface on reducing soil resistance to disc ploughing

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Science China(Technological Sciences) 2010年第11期53卷 2960-2965页

作者： CHIRENDE Benard SIMALENGA Timothy Emmanuel Key Laboratory for Bionic Engineering of Ministry of Education of China Jilin University Agricultural Research Council Institute for Agricultural Engineering(South Africa)

Past researches have shown that the non-smooth body surfaces of soil burrowing animals help to reduce soil resistance. In this research, this concept of bionic non-smooth surface was applied to disc ploughs and an experiment was conducted in an indoor soil bin to find out the effects of different bionic units on reducing soil resistance to disc ploughing. Horizontal force acting on the disc plough during soil deformation was measured using a 5 kN sensor. Convex and concave bionic units were used and the material used for making convex ones is ultra high molecular weight polyethylene (UHMWPE) which is hydrophobic. From the experiment results, higher or deeper bionic units always resulted in less soil resistance. Convex bionic units gave the highest resistance reduction reaching a maximum of 19% reduction (from 1715.36 N to 1383.65 N) compared to concave bi-onic units. Also, samples with a bionic unit density of 30% gave the highest resistance reduction compared to the other two, which were either plain or had 10% density. In conclusion, the concept of bionic non-smooth units can be applied to disc ploughs in order to reduce soil resistance.

关键词： bionics disc plough soil resistance convex units concave units non-smooth surface

Three-Dimensional Geometrical Modelling of Wild Boar Head by Reverse Engineering Technology

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Journal of Bionic Engineering 2008年第1期5卷 85-90页

作者： Liang Xn Min-xu Lin Jian-qiao Li Zhao-liang Wang B. Chirende Key Laboratory of Terrain-Machine Bionics Engineering （Ministry of Education China） Jilin University Changchun 130022 P. R. China Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 P R. China

In this paper, a wild boar head was taken as the bionic research object for the development of new ridgers, a kind of plough. The reverse engineering technology was adopted to obtain the surface geometrical information of the head. Several three-dimensional （3D） point clouds of the head were captured first using a non-touch laser scanner, and an integrated point cloud was generated by aligning these point clouds using UG/Imageware. Then, the digital surface model of the head was rebuilt by means of CATIA. The characteristic curves of the surface model were analyzed. The results show that the average error between the rebuilt surface and the point cloud is -0.431 ram. The max curvature of the ridge on the neb of the head is 0.187 mm^-1, and the max and rain Gauss curvatures on the surface are 0.008 mm^-2 and -0.002 mm^-2. These geometrical information are the essential parameters for biomimetics study of the ridger.

关键词： bionics reverse engineering surface modeling numerical analysis ridger plough

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小流域经济与市场经济联结之浅见

中国水土保持 1995年第8期 51-53页

作者：李秋兰山东省水土保持办公室

小流域经济与市场经济联结之浅见李秋兰（山东省水土保持办公室，济南２５００１３）原水利部部长杨振怀同志于１９９３年撰文指出：“把水土保持引向市场经济是实现９０年代水土流失防治目标的关键。水土保持要适应社会主义市场经济的... 详细信息

小流域经济与市场经济联结之浅见李秋兰（山东省水土保持办公室，济南２５００１３）原水利部部长杨振怀同志于１９９３年撰文指出：“把水土保持引向市场经济是实现９０年代水土流失防治目标的关键。水土保持要适应社会主义市场经济的发展，否则将失去生存和发展的条件，...

关键词： ] soil and water conservation plough measure " rat road" ploughing techniquethe benefit of output increase

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Characterization of Leaf Photosynthetic Properties for No-Tillage Rice

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Rice science 2007年第4期14卷 283-288页

作者： CHEN Song XIA Guo-mian ZHAO Wei-ming WU Fei-bo ZHANG Guo-ping Agronomy Department Zhejiang University Hangzhou 310029 China Agricultural Bureau of Xiaoshan Zhejiang Province Xiaoshan 311203 China Agricultural Bureau of Zhejiang Province Hangzhou 310021 China

A study was conducted to determine the influence of no-tillage cultivation on leaf photosynthesis of rice plants under field conditions. Experiments with the treatments, no-tillage and conventional tillage were carried out at three locations （Jiaxing, Hangzhou and Xiaoshan, Zhejiang Province, China） for two years （2005 and 2006）. Grain yield was constant in Jiaxing, but slightly higher in Hangzhou and Xiaoshan under no-tillage cultivation than that under conventional cultivation. In comparison with the conventional cultivation, no-tillage cultivation showed less biomass accumulation before heading and higher capacity of matter production during grain filling. A significantly higher leaf net photosynthetic rate was observed for the plants under no-tillage than for those under conventional tillage. The fluorescence parameter （Fv/Fm） in leaf did not show any difference between the two cultivations. The effect of cultivation management on transpiration rate （Tr） and SPAD value of rice leaf was dependent on the location and year.

关键词： photosynthesis leaf rice no-tillage plough yield

THE APPLICATION OF SATELLITE POSITIONING TECHNOLOGY AND ITS INDUSTRIALIZATION IN CHINA

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空间科学学报 2002年第Z1期22卷 177-184页

作者： ZHENG Lizhong CHEN Xiuwan National Remote Sensing Center of China Ministry of Science and Technology Beijing 100862 P.R. China National Remote Sensing Center of China Ministry of Science and Technology Beijing 100862 P.R. China Institute of Remote Sensing and GIS Peking University P.R. China

Satellite positioning technology has been widely used in all kinds of military and civil land, marine, space and aeronautical target positioning tasks, naviga tion activities and accurate surveying measurements since 90 s in the last cen tury due to its advantage in providing all-weather, real-time, three dimensional and high precision positioning information, as well as speed and accurate timing information. By now, it has already formed a new hi-tech industry *** paper briefly reviews the development of the global satellite positioning and navigation technologies including the basic information of China's "plough navigation system", introduces the history of satellite positioning technology and its major application fields as well as the status quo of this being industri alized trade in China, gives an account of the writers' vision for the application and prospect of the satellite positioning technologies in China, and approaches the tactics and stresses of the satellite positioning technology's application and its industrialization future in China.

关键词： Satellite positioning technology, Global navigation satellite sys tem(GNSS), plough navigation system, Global Positioning System(GPS), Galileo Plan

Development of an Integrated Tool for Small-Scale Maize Farming in Uganda

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Agricultural Sciences 2020年第7期11卷 653-666页

作者： Louis J. M. Obura Robert K. Kambugu Nicholas Kiggundu Hussein K. Balimunsi Samuel Kyamanywa Department of Agricultural and Biosystems Engineering Makerere University Kampala Uganda Department of Agricultural Engineering University of Juba Juba South Sudan Department of Agricultural Production Makerere University Kampala Uganda

About 62% of the maize produced in developing countries is cultivated manually owing to limited access to appropriate technology. Available technologies perform a single operation, necessitating farmers to buy multiple implements, which is expensive. In this study, an ox-drawn tool integrating a plough, planter and cultivator for small-scale maize farming was developed and its performance evaluated. Planting and cultivating units were designed and fabricated for assembly onto an existing standard ox-plough beam. The integrated tool was tested in the field to assess the effectiveness and efficiency of cultivation and planting of maize. Results showed that the planting unit had an average seed rate of 35.4 kg/ha with a seed damage of 4% and an effective field capacity of 0.15 ha/h at a field efficiency of 87.3%. The cultivating unit had an effective field capacity of 0.1 ha/h and a weeding efficiency of 86%. The efficiency, effectiveness and reliability for field operations are superior to manual operations currently used by farmers and are comparable to single-unit prototypes developed in other countries. This demonstrates the technical feasibility of integrating planting and cultivation units onto an existing mould board plough instead of buying multiple tools.

关键词： Integrated Tool plough Cultivator Mechanization Smallholder Maize Farming