针对多模态多目标优化中种群多样性难以维持和所得等价Pareto最优解数量不足问题,提出一种融合聚类和小生境搜索的多模态多目标优化算法(multimodal multi-objective optimization algorithm with clustering and niching searching,CSS...针对多模态多目标优化中种群多样性难以维持和所得等价Pareto最优解数量不足问题,提出一种融合聚类和小生境搜索的多模态多目标优化算法(multimodal multi-objective optimization algorithm with clustering and niching searching,CSSMPIO)。首先利用基于聚类的特殊拥挤距离非支配排序方法(clustering-based special crowding distance,CSCD)初始化种群;引入自适应物种形成策略生成稳定的小生境,在不同的小生境子空间并行搜索和保持等价Pareto最优解;采用特殊拥挤距离非支配排序策略实现个体选优、精英学习策略避免过早收敛。通过在14个多模态多目标函数上进行测试,并与7种新提出的多模态多目标优化算法进行对比实验以及Wilcoxon秩和检验发现,CSSMPIO的总体性能优于对比算法。最后将算法用于基于地图的测试问题,进一步证明了算法的有效性。展开更多
为了解决增量流形学习中的噪声干扰,以及对不同分布状态下的新数据进行流形降维问题,本文提出一种数据流形边界及其分布条件的增量式降维算法(incremental dimensionality reduction algorithm based on data manifold boundaries and d...为了解决增量流形学习中的噪声干扰,以及对不同分布状态下的新数据进行流形降维问题,本文提出一种数据流形边界及其分布条件的增量式降维算法(incremental dimensionality reduction algorithm based on data manifold boundaries and distribution state,IDR-DMBDS)。该算法首先分析噪声概率分布同时对数据降噪,确定降噪数据的流形形态为主流形,并在主流形上表征出噪声的分布形式,以此获得近似的原数据流形边界,然后基于流形边界判别新数据的分布状态,最后将分布于原流形形态之上以及之外的新数据分别映射至低维空间。实验表明,该算法能够有效实现基于流形的增量式高维含噪数据的低维特征挖掘。展开更多
The 1050 aluminum alloy strip was prepared by means of electromagnetic and ultrasonic cast rolling on the modified asymmetric twin roll caster, and then the aluminum substrate for presensitized plate was prepared thro...The 1050 aluminum alloy strip was prepared by means of electromagnetic and ultrasonic cast rolling on the modified asymmetric twin roll caster, and then the aluminum substrate for presensitized plate was prepared through cold rolling and annealing.The effects of electromagnetic and ultrasonic cast rolling on microstructure, mechanical properties, surface roughness and electrolytic corrosion properties of 1050 aluminum substrate were studied. The results show that electromagnetic and ultrasonic cast rolling can decrease the average crystallite size of aluminum substrate by 5 μm, increase the crystal boundaries with uniform distribution, and make the second-phase particles with smaller size distributed dispersively in the substrate, meanwhile, it can increase the tensile strength, elongation and micro-hardness by 4.58%, 9.85% and HV 2, respectively, reduce the surface roughness, make the surface appearance more even, electrolytic corrosion polarization curve of aluminum substrate more smooth and the surface corrosion pits with regular shape more dispersive.展开更多
文摘针对多模态多目标优化中种群多样性难以维持和所得等价Pareto最优解数量不足问题,提出一种融合聚类和小生境搜索的多模态多目标优化算法(multimodal multi-objective optimization algorithm with clustering and niching searching,CSSMPIO)。首先利用基于聚类的特殊拥挤距离非支配排序方法(clustering-based special crowding distance,CSCD)初始化种群;引入自适应物种形成策略生成稳定的小生境,在不同的小生境子空间并行搜索和保持等价Pareto最优解;采用特殊拥挤距离非支配排序策略实现个体选优、精英学习策略避免过早收敛。通过在14个多模态多目标函数上进行测试,并与7种新提出的多模态多目标优化算法进行对比实验以及Wilcoxon秩和检验发现,CSSMPIO的总体性能优于对比算法。最后将算法用于基于地图的测试问题,进一步证明了算法的有效性。
文摘为了解决增量流形学习中的噪声干扰,以及对不同分布状态下的新数据进行流形降维问题,本文提出一种数据流形边界及其分布条件的增量式降维算法(incremental dimensionality reduction algorithm based on data manifold boundaries and distribution state,IDR-DMBDS)。该算法首先分析噪声概率分布同时对数据降噪,确定降噪数据的流形形态为主流形,并在主流形上表征出噪声的分布形式,以此获得近似的原数据流形边界,然后基于流形边界判别新数据的分布状态,最后将分布于原流形形态之上以及之外的新数据分别映射至低维空间。实验表明,该算法能够有效实现基于流形的增量式高维含噪数据的低维特征挖掘。
基金Project(2014CB046702) supported by the National Basic Research Program of ChinaProject supported by the Postdoctoral Science Foundation of Central South University,China
文摘The 1050 aluminum alloy strip was prepared by means of electromagnetic and ultrasonic cast rolling on the modified asymmetric twin roll caster, and then the aluminum substrate for presensitized plate was prepared through cold rolling and annealing.The effects of electromagnetic and ultrasonic cast rolling on microstructure, mechanical properties, surface roughness and electrolytic corrosion properties of 1050 aluminum substrate were studied. The results show that electromagnetic and ultrasonic cast rolling can decrease the average crystallite size of aluminum substrate by 5 μm, increase the crystal boundaries with uniform distribution, and make the second-phase particles with smaller size distributed dispersively in the substrate, meanwhile, it can increase the tensile strength, elongation and micro-hardness by 4.58%, 9.85% and HV 2, respectively, reduce the surface roughness, make the surface appearance more even, electrolytic corrosion polarization curve of aluminum substrate more smooth and the surface corrosion pits with regular shape more dispersive.
