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我国铅资源开发现状和可持续发展建议 被引量:17
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作者 顾亚 王建平 +2 位作者 王修 车东 吴起鑫 《资源与产业》 2018年第1期39-46,共8页
通过收集整理近十年铅资源相关统计数据,从我国铅资源的储量、产量、供需关系、进出口及市场价格等方面着手,深入分析我国铅资源的开发现状,指出我国铅资源开发中存在的问题,并给出了针对性的建议。我国是世界铅资源大国,储量位居世界前... 通过收集整理近十年铅资源相关统计数据,从我国铅资源的储量、产量、供需关系、进出口及市场价格等方面着手,深入分析我国铅资源的开发现状,指出我国铅资源开发中存在的问题,并给出了针对性的建议。我国是世界铅资源大国,储量位居世界前列,产量和消费量均居世界首位。我国铅资源开发存在资源保障程度偏低、矿石依赖进口严重、再生铅业发展滞后、环境污染严重等问题。针对上述问题,提出了以下可持续发展建议:加强找矿勘查,提高资源储量;增强国际合作,减少矿石依赖;加快发展再生铅产业,高效利用资源;严格监督执法,保护资源环境。 展开更多
关键词 铅资源 资源现状 可持续发展 中国
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Optimizing selection of bridge raft based on fuzzy matter-element model and combination weighting
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作者 Li Feng Shao Fei +1 位作者 wang jianping Li Zhigang 《Engineering Sciences》 EI 2012年第1期61-64,96,共5页
It' s a necessary selection to support the maneuver across Yangtze River by floating bridge constructed by portable steel bridge and civilian ships. It is a comprehensive index for the scheme of bridge raft, containi... It' s a necessary selection to support the maneuver across Yangtze River by floating bridge constructed by portable steel bridge and civilian ships. It is a comprehensive index for the scheme of bridge raft, containing a variety of technical factors and uncertainties. The optimization is the selection in the constructing time, quantity of equipments and man power. Based on the calculation result of bridge rafts, an evaluating system is established, consisting of index of spacing between interior bays, raft length, truss numbers, operation difficulty and maximal bending stress. A fuzzy matter element model of optimizing selection of bridge rafts was built up by combining quantitative analysis with qualitative analysis. The method of combination weighting was used to calculate the value of weights index to reduce the subjective randomness. The sequence of schemes and the optimization resuh were gained finally based on euclid approach degree. The application result shows that it is simple and practical. 展开更多
关键词 bridge raft optimizing selection fuzzy matter-element combination weighting euclid approach degree
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