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刘海威 《青海师范大学学报(自然科学版)》2005,(3):109-112
西部民族地区自然生态保护和畜牧业生产方面,存在一些突出问题:草原生态不断恶化。人畜、草畜、畜牧业生产方式、劳动者现代文化素质、产业结构、经济收入。发展失调,其矛盾日益尖锐.为了改善自然生态平衡,切实解决“三农”问题.增加农牧民收入。坚持以人为本,依靠科学进步,构建人与自然和谐相处的环境,保障西部地区社会可持续发展. 相似文献
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Some mechanisms evolve from other mechanisms to fulfil a new function. It follows that there is cognation between certain mechanisms. Addressed in the present paper are innovative design methods for displacement machinery. According to the design of the changeable displacement pump, it may be a closed pair of components in the mechanism that possesses periodically relative movement to form a periodically changeable and closed cavity. To this can be adapted design methods based on innovative theories, such as the Scotch Cousin theory in evolution venations, the theory of Cognation, the theory of “Nodes“ among generations and so on. Thus innovative designs for them can be produced by imaginative thinking. Illustrated here is an innovative design for a pump a with half-sphere rotor, developed from a typical 4-bar mechanism in accordance with the principle of Precession Evolution, which is to be applied to the recovery of oil spillage at sea. 相似文献
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