横梁是龙门加工中心关键部件之一,其静动态特性直接关系到整机性能。文章在ANSYS Space Claim环境下建立横梁实体模型,运用workbench进行横梁静动态分析计算,并在其基础上利用响应面法对其进行优化设计。改进横梁的肋板结构尺寸,提高性...横梁是龙门加工中心关键部件之一,其静动态特性直接关系到整机性能。文章在ANSYS Space Claim环境下建立横梁实体模型,运用workbench进行横梁静动态分析计算,并在其基础上利用响应面法对其进行优化设计。改进横梁的肋板结构尺寸,提高性能,为横梁优化提供了理论依据。展开更多
Machine learning models are constructed to predict fragment production cross sections in projectile fragmentation(PF)reactions using Bayesian neural network(BNN)techniques.The massive learning for BNN models is based ...Machine learning models are constructed to predict fragment production cross sections in projectile fragmentation(PF)reactions using Bayesian neural network(BNN)techniques.The massive learning for BNN models is based on 6393 fragments from 53 measured projectile fragmentation reactions.A direct BNN model and physical guiding BNN via FRACS parametrization(BNN+FRACS)model have been constructed to predict the fragment cross section in projectile fragmentation reactions.It is verified that the BNN and BNN+FRACS models can reproduce a wide range of fragment productions in PF reactions with incident energies from 40 MeV/u to 1 GeV/u,reaction systems with projectile nuclei from^40 Ar to^208 Pb,and various target nuclei.The high precision of the BNN and BNN+FRACS models makes them applicable for the low production rate of extremely rare isotopes in future PF reactions with large projectile nucleus asymmetry in the new generation of radioactive nuclear beam factories.展开更多
正交异性板各个构件的选用关系着钢桥面系的安全性及经济性,通过有限元分析软件,建立桥面系板单元模型,对正交异性板多横梁体系纵梁、纵肋高度变化时桥面系各部分受力分析,总结纵梁（肋）高度变化对桥面板、横梁以及横梁与纵梁（肋）相...正交异性板各个构件的选用关系着钢桥面系的安全性及经济性,通过有限元分析软件,建立桥面系板单元模型,对正交异性板多横梁体系纵梁、纵肋高度变化时桥面系各部分受力分析,总结纵梁（肋）高度变化对桥面板、横梁以及横梁与纵梁（肋）相交处挖孔部位受力的影响趋势,得出结论：增加纵梁高度,纵梁自身正应力逐渐增大,U 肋正应力逐渐减小;横梁U 肋挖孔处主拉应力增大,横肋相应处主拉应力减小,但减小或增大的幅度较小.改变T 形纵梁高度,对横梁整体受力及桥面板影响甚小,可忽略不计, T 形纵梁的合理取值范围为横梁高度的0.35-0 . 4倍; U 肋高度过大或者过小,桥面板应力的均匀性均不好,且主拉应力均较大.增大U 肋高度,纵梁正应力逐渐减小, U 肋自身应力并未成线性变化趋势,而是呈“锯齿”形变化趋势.改变U 肋高度对桥面板应力影响均较小,可忽略不计, U 肋的合理高度取值范围为240-280 mm.展开更多
基金Supported by the National Natural Science Foundation of China(11975091)the Program for Innovative Research Team(in Science and Technology)in University of Henan Province(21IRTSTHN011),China。
文摘Machine learning models are constructed to predict fragment production cross sections in projectile fragmentation(PF)reactions using Bayesian neural network(BNN)techniques.The massive learning for BNN models is based on 6393 fragments from 53 measured projectile fragmentation reactions.A direct BNN model and physical guiding BNN via FRACS parametrization(BNN+FRACS)model have been constructed to predict the fragment cross section in projectile fragmentation reactions.It is verified that the BNN and BNN+FRACS models can reproduce a wide range of fragment productions in PF reactions with incident energies from 40 MeV/u to 1 GeV/u,reaction systems with projectile nuclei from^40 Ar to^208 Pb,and various target nuclei.The high precision of the BNN and BNN+FRACS models makes them applicable for the low production rate of extremely rare isotopes in future PF reactions with large projectile nucleus asymmetry in the new generation of radioactive nuclear beam factories.
文摘正交异性板各个构件的选用关系着钢桥面系的安全性及经济性,通过有限元分析软件,建立桥面系板单元模型,对正交异性板多横梁体系纵梁、纵肋高度变化时桥面系各部分受力分析,总结纵梁（肋）高度变化对桥面板、横梁以及横梁与纵梁（肋）相交处挖孔部位受力的影响趋势,得出结论：增加纵梁高度,纵梁自身正应力逐渐增大,U 肋正应力逐渐减小;横梁U 肋挖孔处主拉应力增大,横肋相应处主拉应力减小,但减小或增大的幅度较小.改变T 形纵梁高度,对横梁整体受力及桥面板影响甚小,可忽略不计, T 形纵梁的合理取值范围为横梁高度的0.35-0 . 4倍; U 肋高度过大或者过小,桥面板应力的均匀性均不好,且主拉应力均较大.增大U 肋高度,纵梁正应力逐渐减小, U 肋自身应力并未成线性变化趋势,而是呈“锯齿”形变化趋势.改变U 肋高度对桥面板应力影响均较小,可忽略不计, U 肋的合理高度取值范围为240-280 mm.
