期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
改进蚁群优化算法求解折扣{0-1}背包问题
1
作者 张铭 邓文瀚 +1 位作者 林娟 钟一文 《计算机工程与应用》 CSCD 北大核心 2021年第13期85-95,共11页
折扣{0-1}背包问题(Discounted{0-1}Knapsack Problem,DKP)是一个NP-困难的组合优化问题,尽管已经存在一些求解DKP的智能优化算法,但目前尚没有用蚁群优化(Ant Colony Optimization,ACO)算法求解DKP的研究。提出了一个求解DKP的改进ACO(... 折扣{0-1}背包问题(Discounted{0-1}Knapsack Problem,DKP)是一个NP-困难的组合优化问题,尽管已经存在一些求解DKP的智能优化算法,但目前尚没有用蚁群优化(Ant Colony Optimization,ACO)算法求解DKP的研究。提出了一个求解DKP的改进ACO(Modified ACO,MACO)算法。MACO算法使用整数编码以保证每组物品最多只有一个物品被选中,在MACO算法构造解的每一步,采用组内竞争选择来降低算法的时间复杂性,对计算选择概率的公式,放弃启发式信息以减少参数并简化算法参数设置,对蚂蚁构造出的解,经修复后使用基于价值密度和价值的混合贪婪优化算子来提高算法的寻优能力。在四类测试用例上对MACO算法进行了测试并与其他算法进行比较,实验结果表明MACO算法的性能明显优于其他算法。 展开更多
关键词 折扣{0-1}背包问题(DKP) 蚁群优化算法(ACO) 信息素 组内选择 混合优化
下载PDF
Interspecific Hybridization Between Crassostrea angulata and C. ariakensis 被引量:2
2
作者 YAO Tuo ZHANG Yuehuan +4 位作者 YAN Xiwu WANG Zhaoping LI Dongchun SU Jiaqi YU Ruihai 《Journal of Ocean University of China》 SCIE CAS 2015年第4期710-716,共7页
lnterspecific hybridization can generate heterosis, which is proven to be a useful tool in selective breeding programs for oyster culture. Crassostrea angulata and C. ariakensis are two important economic shellfish sp... lnterspecific hybridization can generate heterosis, which is proven to be a useful tool in selective breeding programs for oyster culture. Crassostrea angulata and C. ariakensis are two important economic shellfish species in China. We conducted 2 × 2 reciprocal crosses to determine whether these two species can cross-fertilize and their hybrids can hatch, survive and perform hetero- sis. Fertilization was found symmetrical without delay. The rate of fertilization success of C. angulata ♀× C. ariakensis ♂ was lower than that of C. ariakensis ♀ x C. angulata ♂, and the success rate of both hybridizations was lower than that of two intraspecific crosses each. During the planktonic period, survival rate of the progeny was lower in the hybrid crosses than in the intraspecific crosses. On day 360, mean shell height of the progeny of C. angulata ♀ x C. angulata ♂ was highest, which was followed by that of C. angulata ♀ × C. ariakensis ♂, C. ariakensis ♀x C. ariakensis ♂ and C. ariakensis ♀× C. angulata ♂ in a descending order. Mor- phology of adults produced by the hybrid crosses was similar to that of C. angulata. Both hybrids underwent normal gonad devel- opment and produced mature gametes in the mating season. This study provided new insights into the quantitative traits in interspeci- fic crosses of Crassostrea species, thus being of guidance value for selective breeding of oyster. 展开更多
关键词 Crassostrea angulata Crassostrea ariakensis interspecific hybridization gonad development HETEROSIS
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部