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某型固体火箭发动机的可靠性增长分析 被引量:3
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作者 安伟光 周源泉 《推进技术》 EI CAS CSCD 北大核心 1997年第4期14-17,共4页
对某型固体火箭发动机的可靠性增长进行了统计检验,在可靠性增长的基础上,用二项分布阶段可靠性增长的Bayes方法评定了该机的可靠性下限。结果表明,可靠性增长方法能充分利用信息,并可节省大量试验样本。
关键词 固体推进剂 固体火箭发动机 可增性增长 分析
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Zero Growth of Chemical Fertilizer and Pesticide Use: China's Objectives, Progress and Challenges 被引量:40
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作者 金书秦 周芳 《Journal of Resources and Ecology》 CSCD 2018年第1期50-58,共9页
In 2015 China’s Ministry of Agriculture introduced two Actions that seek to achieve zero growth in the use of chemical fertilizer and pesticides by 2020. Success in reaching these targets will help control agricultur... In 2015 China’s Ministry of Agriculture introduced two Actions that seek to achieve zero growth in the use of chemical fertilizer and pesticides by 2020. Success in reaching these targets will help control agricultural non-point source pollution, increase cost efficiency, energy conservation and emission reductions, help to ensure the safety and quality of the national grain supply and agricultural products and the safety of the ecological environment, and realize the sustainable development of agriculture. However, successful implementation will be crucial. This article considers the main contents of the Actions and analyzes their feasibility from the perspectives of policy formulation, local practices, technical support and achievements. We identify problems and challenges and suggest that zero growth of chemical fertilizer and pesticide use can be achieved by undertaking basic research on the factors that shape the use of farm chemicals, making improvements to the monitoring and statistical system for chemical fertilizer and pesticide use, setting up demonstration projects and enhancing policies formulated to reduce chemical fertilizer and pesticide use. 展开更多
关键词 zero growth of chemical fertilizer zero growth of pesticide FEASIBILITY China
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