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四川核桃优良单株选择的研究 被引量:36
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作者 朱益川 赵世远 +3 位作者 文斌 李家荣 何晓章 余军 《四川林业科技》 北大核心 2000年第4期11-15,共5页
1 966年以后 ,在我省重点核桃产区开展优良种质资源选择工作。按坚果品质和丰产性状等选育指标 ,进行优树初选、复选和决选。经多性状综合评定 ,筛选出 1 2株优良单株。所选择的优良单株平均树龄 2 7年 ,株产坚果 2 1 .6kg,树冠投影面... 1 966年以后 ,在我省重点核桃产区开展优良种质资源选择工作。按坚果品质和丰产性状等选育指标 ,进行优树初选、复选和决选。经多性状综合评定 ,筛选出 1 2株优良单株。所选择的优良单株平均树龄 2 7年 ,株产坚果 2 1 .6kg,树冠投影面积产仁量 0 .2 65kg/ m2 ,平均单果重 1 2 .4 5g,壳厚度 1 .0 7mm,出仁率 60 .2 5%。用这批优良单株作为无性繁殖材料 ,是改良我省核桃遗传品质、提高核桃生产效益的重要途径之一。 展开更多
关键词 核桃 优良单株 优权选择 多性状综合评定 品质性状 丰产性状
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Improved Whale Optimization Algorithm Based on Mirror Selection 被引量:5
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作者 LI Jingnan LE Meilong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第S01期115-123,共9页
Since traditional whale optimization algorithms have slow convergence speed,low accuracy and are easy to fall into local optimal solutions,an improved whale optimization algorithm based on mirror selection(WOA-MS)is p... Since traditional whale optimization algorithms have slow convergence speed,low accuracy and are easy to fall into local optimal solutions,an improved whale optimization algorithm based on mirror selection(WOA-MS)is proposed. Specific improvements includes:(1)An adaptive nonlinear inertia weight based on Branin function was introduced to balance global search and local mining.(2) A mirror selection method is proposed to improve the individual quality and speed up the convergence. By optimizing several test functions and comparing the experimental results with other three algorithms,this study verifies that WOA-MS has an excellent optimization performance. 展开更多
关键词 inertia weight mirror selection whale optimization algorithm(WOA)
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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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